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From Empathy to Apathy: The Bystander Effect Revisited

Ruud hortensius.

1 Institute of Neuroscience and Psychology, School of Psychology, University of Glasgow

Beatrice de Gelder

2 Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University

3 Department of Computer Science, University College London

The bystander effect, the reduction in helping behavior in the presence of other people, has been explained predominantly by situational influences on decision making. Diverging from this view, we highlight recent evidence on the neural mechanisms and dispositional factors that determine apathy in bystanders. We put forward a new theoretical perspective that integrates emotional, motivational, and dispositional aspects. In the presence of other bystanders, personal distress is enhanced, and fixed action patterns of avoidance and freezing dominate. This new perspective suggests that bystander apathy results from a reflexive emotional reaction dependent on the personality of the bystander.

When people are asked whether they would spontaneously assist a person in an emergency situation, almost everyone will reply positively. Although we all imagine ourselves heroes, the fact is that many people refrain from helping in real life, especially when we are aware that other people are present at the scene. In the late 1960s, John M. Darley and Bibb Latané (1968) initiated an extensive research program on this so-called “bystander effect.” In their seminal article, they found that any person who was the sole bystander helped, but only 62% of the participants intervened when they were part of a larger group of five bystanders. Following these first findings, many researchers consistently observed a reduction in helping behavior in the presence of others ( Fischer et al., 2011 ; Latané & Nida, 1981 ). This pattern is observed during serious accidents ( Harris & Robinson, 1973 ), noncritical situations ( Latané & Dabbs, 1975 ), on the Internet ( Markey, 2000 ), and even in children ( Plötner, Over, Carpenter, & Tomasello, 2015 ).

Three psychological factors are thought to facilitate bystander apathy: the feeling of having less responsibility when more bystanders are present ( diffusion of responsibility ), the fear of unfavorable public judgment when helping ( evaluation apprehension ), and the belief that because no one else is helping, the situation is not actually an emergency ( pluralistic ignorance ). Although these traditional explanations ( Latané & Darley, 1970 ) cover several important aspects (attitudes and beliefs), other aspects remain unknown, unexplained, or ignored in studies of the bystander effect, including neural mechanisms, motivational aspects, and the effect of personality. Indeed, the only hit for the keyword “personality” in a recent overview ( Fischer et al., 2011 ) was for journal names in the reference list (e.g., Journal of Personality and Social Psychology ). Consequently, it seems fair to say that the “literature has remained somewhat ambiguous with regard to the relevant psychological processes” ( Fischer et al., 2011 , p. 518). Here, we highlight recent neuroimaging and behavioral studies and sketch a new theoretical model that incorporates emotional, motivational, and dispositional aspects and highlights the reflexive aspect of the bystander effect.

Neural Mechanisms of Bystander Apathy

Can neuroimaging studies inform the investigation of the bystander effect? What are the neural mechanisms underlying bystander apathy? In view of traditional explanations, one would expect to find the involvement of brain regions that are important for decision making. Yet emerging evidence suggests that certain forms of helping behavior are automatic or reflexive ( Rand, 2016 ; Zaki & Mitchell, 2013 ), and recent neuroimaging studies without a bystander focus already propose the automatic activation of preparatory responses in salient situations. Observing a threatening confrontation between two people activates the premotor cortex independent of attention ( Sinke, Sorger, Goebel, & de Gelder, 2010 ) or focus ( Van den Stock, Hortensius, Sinke, Goebel, & de Gelder, 2015 ). This raises the question of whether the absence of helping behavior is a cognitive decision or follows automatically from a reflexive process.

A recent functional MRI (fMRI) study directly mapped neural activity as a function of the number of bystanders present in an emergency situation ( Hortensius & de Gelder, 2014 ). Participants watched an elderly woman collapsing to the ground alone or in the presence of one, two, or four bystanders. Activity increased in vision- and attention-related regions, but not in the mentalizing network. When participants witnessed emergencies with increasing numbers of bystanders, a decrease in activity was observed in brain regions important for the preparation to help: the pre- and postcentral gyrus and the medial prefrontal cortex (MPFC; Fig. 1a ). The MPFC is implicated in a diverse set of emotional and social processes. One proposal for an overarching role is mapping of situation-response association ( Alexander & Brown, 2011 ; Euston, Gruber, & McNaughton, 2012 ), coding the link between an event (e.g., an emergency) and corresponding responses (in this case, helping behavior). Activity in the MPFC has been linked to prosocial behavior ( Moll et al., 2006 ; Rilling et al., 2002 ; Waytz, Zaki, & Mitchell, 2012 ), such as helping friends and strangers on a daily basis ( Rameson, Morelli, & Lieberman, 2012 ).

Neural activity as it relates to bystander apathy. In a functional magnetic resonance imaging experiment testing bystander apathy (a), participants saw an elderly woman collapsing on the ground in the presence of no, one, two, or four bystanders. Still images from the videos are shown. The decrease in activity in the pre- and postcentral gyrus and the medial prefrontal cortex during the witness of an emergency with increasing number of bystanders is shown. In a virtual reality experiment (b), participants had to evacuate a burning building. During the evacuation, they encountered a trapped individual whom they could help or not. Still images from the virtual reality environment are shown. Increased functional coupling of the medial prefrontal cortex within the anterior part of the default-mode network in individuals who helped compared with individuals who did not help is shown. Panel (a) was adapted from Hortensius and de Gelder (2014) , and panel (b) was adapted from  Zanon, Novembre, Zangrando, Chittaro, and Silani (2014) ; both are reproduced with permission from Elsevier.

Using a scenario similar to those used in early bystander studies, Zanon, Novembre, Zangrando, Chittaro, and Silani (2014) showed the importance of the MPFC for helping behavior during a life-threatening situation. In an experiment using virtual reality, participants and four bystanders had to evacuate a building that caught on fire. While doing so, they encountered a trapped individual whom they could help. People who offered to help (compared with those who refrained from helping) showed greater engagement of the MPFC within the anterior default-mode network ( Fig. 1b ). However, can this association be quantified as reflexive or reflective? A recent study suggests that computations underlying choices with a focus on other people’s needs are faster, or reflexive, compared with computations of choices with a selfish focus ( Hutcherson, Bushong, & Rangel, 2015 ). Both of these choices are sustained by the MPFC. Recent evidence suggests that coding of reflexive responses to situations within this area might depend on experience and personality. When cognition was restricted while participants observed people in distress, activity in the MPFC did not decrease for people with higher levels compared with people with lower levels of dispositional empathy ( Rameson et al., 2012 ). Together, these recent findings provide a first indication of the neural mechanism underlying bystander apathy and point to a possible mechanism similar to a reflex that determines the likelihood of helping.

Dispositional Influences on Bystander Apathy

The first experimental bystander study found no effect of dispositional levels of social-norm following on bystander apathy ( Darley & Latané, 1968 ), and since then the role of personality factors has largely been ignored. The general notion is that behavior is dominated by situational factors rather than by personality; thus bystander apathy is present in everyone. This contrasts with other research areas, in which the impact of personality—systematic interindividual differences consistent across time and situation—on helping behavior have been widely appreciated ( Graziano & Habashi, 2015 ). Sympathy and personal distress have been identified as two dispositional factors that influence helping behavior ( Batson, Fultz, & Schoenrade, 1987 ; Eisenberg & Eggum, 2009 ). Sympathy is an other-oriented response that encompasses feelings of compassion and care for another person. The contrasting and automatic reaction of personal distress relates to the observer’s self-oriented feelings of discomfort and distress. In stark contrast to personal distress, helping behavior driven by sympathy is not influenced by social factors such as social evaluation or reward ( Fultz, Batson, Fortenbach, McCarthy, & Varney, 1986 ; Romer, Gruder, & Lizzadro, 1986 ).

Inspired by these findings, we studied the interplay between the bystander effect and a disposition to experience sympathy and personal distress by directly and indirectly probing the motor cortex while participants observed an emergency ( Hortensius, Schutter, & de Gelder, 2016 ). As predicted by previous literature, both sympathy and personal distress were related to faster responses to an emergency without bystanders present. However, only personal distress predicted the negative effect of bystanders during an emergency. Further testing showed that this association between personal distress and the bystander effect relates to a reflexive—but not reflective—preparation to help. Consistent with the previous neuroimaging findings, bystander apathy is not the result of a cognitive decision to act; rather, it is dependent on a mechanism similar to a reflex, especially for people with a disposition to experience personal distress.

The reflexive aversive reactions to the suffering of another person are closely related to behavioral avoidance and inhibition. Indeed, state and trait avoidance-related motivations influence bystander apathy ( van den Bos, Müller, & van Bussel, 2009 ; Zoccola, Green, Karoutsos, Katona, & Sabini, 2011 ). When people are reminded to act without inhibition, thereby temporally shifting the balance between approach and avoidance motivations, helping behavior occurs faster and even increases in bystander situations ( van den Bos et al., 2009 ). Behavioral inhibition is sustained by subcortical brain regions (e.g., amygdala) and cortical brain regions (e.g., motor and prefrontal areas) that act depending on situation and disposition ( McNaughton & Corr, 2004 ). For example, a recent study showed the dynamic interplay between behavioral inhibition, helping behavior, and personality ( Stoltenberg, Christ, & Carlo, 2013 ). Variation in the serotonin neurotransmitter system, a crucial modulator of behavioral inhibition, affected helping behavior, and this relation was mediated by dispositional levels of social inhibition. Thus, bystander apathy is likely to be the result of a personality-dependent mechanism that is similar to a reflex.

Bystander Apathy as the Result of a Motivational System

These findings dovetail with a motivational model described by Graziano and his colleagues ( Graziano & Habashi, 2010 , 2015 ) in which two evolutionarily conserved but opposing motivational systems with fixed behavioral consequences are activated in sequence when people encounter an emergency. Feelings of personal distress and sympathy are related to the first and second systems, respectively. The instantaneous response to an emergency is a feeling of distress and activation of the fight-freeze-flight system. Under these conditions, helping behavior does not occur, and the behavioral response is limited to avoidance and freeze responses. Over time, a slower feeling of sympathy arises together with the activation of a reflective second system. This counteracts the fixed action patterns of the first system. The likelihood that helping behavior will occur is the net result of these two systems, and helping behavior is promoted by the second system. Feelings of personal distress and sympathy are present in everyone, but the dispositional levels of these feelings and strength of these two systems vary between individuals ( Graziano & Habashi, 2010 , 2015 ). The presence of bystanders during an emergency selectively increases the activity of the first system ( Fig. 2a ). This situational increase in personal distress, combined with dispositional levels of personal distress, increases the activation of the fight-freeze-flight system and results in a reduced likelihood of helping. Indeed, higher levels of personal distress decrease helping behavior when the possibility of escaping the situation is easy ( Batson et al., 1987 ). Ultimately, bystander apathy occurs as the consequence of an inhibitory response, leading people to try to avoid the situation, but this is not a conscious decision.

A motivational and integrated account of bystander apathy. Helping behavior is the net result of two opposing processes ( Graziano & Habashi, 2010 ). When people encounter an emergency, self-centered feelings of personal distress arise, and the fight-freeze-flight system is activated; helping behavior does not occur (a). Only with the opposing other-oriented feeling of sympathy and the activation of the second system does the likelihood of helping increase. The strength of the two systems is the sum of dispositional and situational influences. The strength of System I is increased for people with a disposition to experience personal distress in response to an emergency. Because the presence of bystanders results in an additional increase in the strength and dominance of System I, individuals with a disposition to experience personal distress in response to an emergency are more prone to bystander apathy. Intermediate processes can be described to reconcile cognitive and motivational accounts of bystander apathy. The decision process, as first put forward by Latané and Darley (1970) , consists of the cognitive steps that occur from the initial attentional capture and evaluation of the emergency, to the decision of responsibility and competence, and ultimately to the decision to provide help (b). These processes can be mediated by the integrative processes of behavioral inhibition, emotion regulation. and perspective taking, which are at first driven by the reflexive system of personal distress and later by the reflective system of sympathy. Ultimately, these personality- and situation-dependent processes can increase or decrease the likelihood of a person providing help during emergency situations involving bystanders.

The Ultimate Cause of Bystander Apathy

Although this perspective provides new insight into the proximate cause of bystander apathy, it also allows for speculation on its ultimate cause. Why is the motivation to help dependent on the number of bystanders? Perhaps because, for the best outcome, only the fittest individual (strongest, most experienced, etc.) should provide help and others should not, or at least they should help more cautiously. The training of firefighters and other first responders directly follows these principles: Only well-trained individuals are allowed to help, and trainees are excluded. Taking into account the composition and size of the bystander group is crucial in providing efficient help that maximizes individual survival. This might already be reflected in the calculations within the motivational system ( Francis, Gummerum, Ganis, Howard & Terbeck, 2017 ). Apathy in novel situations or with unknown bystanders could be the consequence of these calculations. There is indirect evidence for this suggestion: Bystander apathy is reduced when bystanders know each other ( Fischer et al., 2011 ), and an individual’s competence relative to other bystanders influences the occurrence of helping behavior ( Bickman, 1971 ; Ross & Braband, 1973 ). Future studies should formally test the effect of group composition (i.e., known identity, expertise) on the calculations within the motivational system. Are increased levels of personal distress during bystander situations a way to prevent inadequate helping behavior?

An Integrative Perspective on Bystander Apathy

This is not to say that previous decision-based explanations are obsolete. Cognitive, situational, and dispositional explanations are not mutually exclusive, and a multilevel approach is crucial in understanding helping behavior and the lack thereof. Thoughts and feelings are part of every responsive bystander, and the motivational processes described could precede or influence the decision to help ( Hortensius, Neyret, Slater & de Gelder, 2018 ). Latané and Darley (1970) describe a five-step process during bystander situations: The potential emergency (a) captures the attention of the individual, who (b) evaluates the emergency, (c) decides on responsibility and (d) belief of competence, and then ultimately (e) makes the decision to help or not. However, these calculations in the decision-making process do not necessarily have to occur at a reflective, cognitive level ( Garcia, Weaver, Moskowitz, & Darley, 2002 ) and can also reflect the outcome of reflexive or intermediate processes.

Several intermediate processes can reconcile the previous reflective and present reflexive explanations but warrant further empirical confirmation ( Fig. 2b ). These processes—behavioral inhibition, emotion regulation, and perspective taking—stem directly from the overarching motivational systems ( Batson et al., 1987 ). Immediately after someone confronts an emergency, the integrative processes (behavioral inhibition and emotion regulation) are under the influence of the first system of personal distress; over time, the system related to sympathy mediates these processes (emotion regulation, perspective taking). Together, these processes increase or decrease bystander apathy. For example, although behavioral inhibition and freezing at an early stage can help in assessing and deciding on the situation ( McNaughton & Corr, 2004 ), prolonged inhibition and freezing is ineffective. Likewise, the ability to regulate initial aversive reactions to an emergency, which are tightly linked to dispositional levels of personal distress and sympathy ( Eisenberg & Eggum, 2009 ), is crucial in deciding to help. Taking into account the perspective of other bystanders, as well as the victim, mediated by the core process of sympathy ( Eisenberg & Eggum, 2009 ), can positively influence felt moral responsibility ( Paciello, Fida, Cerniglia, Tramontano, & Cole, 2013 ), the cognitive belief of competence, and ultimately the decision to help ( Patil et al., 2017 ). This cascade of processes in response to an emergency is reflexive at first, whereas the later stages can be described as reflective. This distinction between reflexive and reflective might be dependent on experience, and the coupling of situation and response can be completely reflexive for certain individuals or situations ( Rand & Epstein, 2014 ; Zaki & Mitchell, 2013 ). As for explaining bystander apathy, however, pluralistic ignorance, evaluation apprehension, and diffusion of responsibility might simply be the summary terms of the attenuated integrative processes of emotion regulation, behavioral inhibition, and perspective taking mediated by the motivational system of personal distress.

Concluding Remarks

This perspective opens up new ways to study the neural and psychological mechanisms of bystander apathy by taking into account situational and dispositional factors. Although ecological validity is a challenge in neuroimaging studies, innovations such as virtual reality, together with neuroimaging and behavioral testing, portable neuroimaging systems, and laboratory-based investigations of people who provided help in real life, will allow the important next steps in bystander research. The bottom-up approach for which we argue sketches a novel perspective on the bystander effect and already paves the way for a different explanation. Together, findings from recent neuroimaging and behavioral studies suggest that the bystander effect is the result of a reflexive action system that is rooted in an evolutionarily conserved mechanism and operates as a function of dispositional personal distress. In the end, we do not actively choose apathy, but are merely reflexively behaving as bystanders.

Recommended Reading

Fischer, P., Krueger, J. I., Greitemeyer, T., Vogrincic, C., Kastenmüller, A., Frey, D., . . . Kainbacher, M. (2011). (See References). A review and meta-analysis of 50 years of research on the bystander effect that provides a critical overview and analysis of factors mitigating bystander apathy.

Hortensius, R., Schutter, D. J. L. G., & de Gelder, B. (2016). (See References). A recent study investigating the influence of a disposition to experience personal distress on bystander apathy by using behavioral and neurophysiological measures.

Preston, S. D. (2013). The origins of altruism in offspring care. Psychological Bulletin, 139 , 1305–1341. A comprehensive and important review on how evolutionarily conserved mechanisms related to offspring care can drive a wide variety of altruistic behaviors in humans.

Slater, M., Rovira, A., Southern, R., Swapp, D., Zhang, J. J., Campbell, C., & Levine, M. (2013). Bystander responses to a violent incident in an immersive virtual environment. PLOS ONE, 8(1) , Article e52766. doi:10.1371/journal.pone.0052766. A first demonstration of how virtual reality can be used to systematically address factors mediating the bystander effect that were hitherto impossible to investigate.

Zanon, M., Novembre, G., Zangrando, N., Chittaro, L., & Silani, G. (2014). (See References). An investigation that used a combination of virtual reality and neuroimaging to elucidate the neural mechanisms underlying the occurrence of helping behavior and show the importance of the medial prefrontal cortex in this process.

Acknowledgments

We thank R. Huiskes and G. J. Will for insightful discussions that further inspired this work and S. Bell for valuable comments on a version of the manuscript.

Action Editor: Randall W. Engle served as action editor for this article.

Declaration of Conflicting Interests: The author(s) declared that there were no conflicts of interest with respect to the authorship or the publication of this article.

Funding: This work was supported by the European Research Council (ERC) under the European Union’s Seventh Framework Programme for Research 2007–13 (ERC Grant agreement numbers 249858 “Tango” and 295673).

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How Psychology Explains the Bystander Effect

How the bystander effect works.

• Real-Life Example
• Explanations

What Is the Meaning of Bystander Effect?

The bystander effect, also known as bystander apathy, refers to a phenomenon in which the greater the number of people there are present, the less likely people are to help a person in distress.

If you witnessed an emergency happening right before your eyes, you would certainly take some sort of action to help the person in trouble, right? While we might all like to believe that this is true, psychologists suggest that whether or not you intervene might depend upon the number of other witnesses present.

When an emergency situation occurs, the bystander effects holds that observers are more likely to take action if there are few or no other witnesses.

Being part of a large crowd makes it so no single person has to take responsibility for an action (or inaction).

In a series of classic studies, researchers Bibb Latané and John Darley found that the amount of time it takes the participant to take action and seek help varies depending on how many other observers are in the room. In one experiment , subjects were placed in one of three treatment conditions: alone in a room, with two other participants, or with two confederates who pretended to be normal participants.

As the participants sat filling out questionnaires, smoke began to fill the room. When participants were alone, 75% reported the smoke to the experimenters. In contrast, just 38% of participants in a room with two other people reported the smoke. In the final group, the two confederates in the experiment noted the smoke and then ignored it, which resulted in only 10% of the participants reporting the smoke.

Additional experiments by Latané and Rodin (1969) found that 70% of people would help a woman in distress when they were the only witness. But only about 40% offered assistance when other people were also present.

What Is a Real-Life Example of the Bystander Effect?

The most frequently cited example of the bystander effect in introductory psychology textbooks is the brutal murder of a young woman named Catherine "Kitty" ​Genovese. On Friday, March 13, 1964, 28-year-old Genovese was returning home from work. As she approached her apartment entrance, she was attacked and stabbed by a man later identified as Winston Moseley.

Despite Genovese’s repeated calls for help, none of the dozen or so people in the nearby apartment building who heard her cries called the police to report the incident. The attack first began at 3:20 AM, but it was not until 3:50 AM that someone first contacted police.

An initial article in the New York Times sensationalized the case and reported a number of factual inaccuracies. An article in the September 2007 issue of American Psychologist concluded that the story is largely misrepresented mostly due to the inaccuracies repeatedly published in newspaper articles and psychology textbooks.  

While Genovese's case has been subject to numerous misrepresentations and inaccuracies, there have been numerous other cases reported in recent years. The bystander effect can clearly have a powerful impact on social behavior, but why exactly does it happen? Why don't we help when we are part of a crowd?

Why Does It Happen?

There are two major factors that contribute to the bystander effect. First, the presence of other people creates a diffusion of responsibility .

Because there are other observers, individuals do not feel as much pressure to take action. The responsibility to act is thought to be shared among all of those present.

The second reason is the need to behave in correct and socially acceptable ways. When other observers fail to react, individuals often take this as a signal that a response is not needed or not appropriate.

Researchers have found that onlookers are less likely to intervene if the situation is ambiguous. In the case of Kitty Genovese, many of the 38 witnesses reported that they believed that they were witnessing a "lover's quarrel," and did not realize that the young woman was actually being murdered.

A crisis is often chaotic and the situation is not always crystal clear. Onlookers might wonder exactly what is happening. During such moments, people often look to others in the group to determine what is appropriate. When they see that no one else is reacting, it sends a signal that perhaps no action is needed.

Preventing the Bystander Effect

What can you do to overcome the bystander effect ? Some psychologists suggest that simply being aware of this tendency is perhaps the greatest way to break the cycle. When faced with a situation that requires action, understand how the bystander effect might be holding you back and consciously take steps to overcome it. However, this does not mean you should place yourself in danger.

But what if you are the person in need of assistance? How can you inspire people to lend a hand? One often recommended tactic is to single out one person from the crowd. Make eye contact and ask that individual specifically for help. By personalizing and individualizing your request, it becomes much harder for people to turn you down.

Manning R, Levine M, Collins A. The Kitty Genovese murder and the social psychology of helping: the parable of the 38 witnesses . Am Psychol. 2007;62(6):555-62. doi:10.1037/0003-066X.62.6.555

Darley JM, Latané B. Bystander “apathy.” American Scientist. 1969;57:244-268.

Latané B, Darley JM. The Unresponsive Bystander: Why Doesn’t He Help?  Prentice Hall, 1970.

Solomon LZ, Solomon H, Stone R. Helping as a function of number of bystanders and ambiguity of emergency . Pers Soc Psychol Bull . 1978;4(2):318-321. doi:10.1177/014616727800400231

By Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

Bystander Effect

Reviewed by Psychology Today Staff

The bystander effect occurs when the presence of others discourages an individual from intervening in an emergency situation, against a bully, or during an assault or other crime . The greater the number of bystanders, the less likely it is for any one of them to provide help to a person in distress. People are more likely to take action in a crisis when there are few or no other witnesses present.

• Understanding the Bystander Effect
• Be an Active Bystander

Social psychologists Bibb Latané and John Darley popularized the concept of the bystander effect following the infamous murder of Kitty Genovese in New York City in 1964. The 28-year-old woman was stabbed to death outside her apartment; at the time, it was reported that dozens of neighbors failed to step in to assist or call the police.

Latané and Darley attributed the bystander effect to two factors: diffusion of responsibility and social influence. The perceived diffusion of responsibility means that the more onlookers there are, the less personal responsibility individuals will feel to take action. Social influence means that individuals monitor the behavior of those around them to determine how to act.

It’s natural for people to freeze or go into shock when seeing someone having an emergency or being attacked. This is usually a response to fear —the fear that you are too weak to help, that you might be misunderstanding the context and seeing a threat where there is none, or even that intervening will put your own life in danger.

It can be hard to tease out the many reasons people fail to take action, but when it comes to sexual assault against women, research has shown that witnesses who are male, hold sexist attitudes, or are under the influence of drugs or alcohol are less likely to actively help a woman who seems too incapacitated to consent to sexual activity.

The same factors that lead to the bystander effect can be used to increase helping behaviors. Individuals are more likely to behave well when they feel themselves being watched by “the crowd,” and when their actions align with their social identities. For example, someone who identifies as pro-environment will take more effort to recycle when they believe they are being observed.

Good people can be complicit in bad behavior (hence the common “just following orders” excuse). Someone who speaks up against bullying is called an “upstander.” Upstanders have confidence in their judgment and values and believe their actions will make a difference. They are more likely to do the right thing because they take the time to stop and think before acting.

The intervention of bystanders is often the only reason why bullying and other crimes cease. The social and behavioral paralysis described by the bystander effect can be reduced with awareness and, in some cases, explicit training. Secondary schools and college campuses encourage students to speak up when witnessing an act of bullying or a potential assault.

One technique is to behave as if one is the first or only person witnessing a problem. Often, when one person takes action, if only to shout, "Hey, what's going on?" or "The police are coming," others may be emboldened to take action as well. That said, an active bystander is most effective when they assume that they themselves are the sole person taking charge; giving direction to other bystanders to assist can, therefore, be critically important.

Don’t expect others to be the first to act in a crisis—just saying “Stop” or “Help is on the way” can prevent further harm. Speak up using a calm, firm tone. Give others directions to get them involved in helping too. Do your best to ensure the safety of the victim, and don’t be afraid to seek assistance when you need it.

If a bystander can help someone without risking their own life and chooses not to, they are usually considered morally guilty. But the average person is typically under no legal obligation to help in an emergency. However, some places have adopted duty-to-rescue laws, making it a crime not to help a person in need.

Yes, some people can be held legally responsible for negative outcomes if they get involved. Fear of legal consequences can be a major contributor to the bystander effect. Some jurisdictions have passed Good Samaritan laws as encouragement for bystanders to act, offering legal protection to those trying to help victims. However, these laws are often limited.

When training yourself to be an active bystander, it helps to cultivate qualities like empathy. Try to see the situation from the victim’s perspective. Worry less about the consequences of helping and more about the example you are setting for future generations. If you are the victim, pick out one person in the crowd and make eye contact. People’s natural tendencies towards altruism may move them to help if given the chance.

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Workplace bullying is a community problem that requires a community response to stop the abuse cycle.

Despite being continually reminded that if we “see something, say something,” most people don’t. Research reveals how to boost benevolent bystander behavior.

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Taking these simple steps to prepare your kids for what to expect as their bodies develop can reduce harm and strengthen your relationship.

Many morally courageous people in history are praised after great sacrifices are made; is there a way for people to support their bravery in the moment instead?

Let’s teach psychology students about the positive aspects of human nature, rather than highlighting the negative. Early flawed theories and studies have "sold human nature short."

A Personal Perspective: I was walking through an airport when I saw someone who I thought may have overdosed. I wasn't sure what to do.

Can you ask for help when you need it? Learn how to ask in an effective and respectful way to get what you need and protect the relationship, too.

Emergencies often feature acts of heroic altruism. Why do people impulsively risk their lives for others? Because we are interconnected through empathy.

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• Bystander Effect And The Diffusion Of Responsibility

The bystander effect is when the presence of others reduces helping behaviours. It is caused partly by a diffusion of responsibility.

The bystander effect in social psychology is the surprising finding that the mere presence of other people inhibits our own helping behaviours in an emergency.

The bystander effect study is mentioned in every psychology textbook and often dubbed ‘seminal’.

This classic social psychology study on the bystander effect was inspired by the highly publicised murder of Kitty Genovese in 1964.

The murder of Kitty Genovese

John Darley and Bibb Latane were inspired to investigate emergency helping behaviours and the bystander effect after the murder of Kitty Genovese in 1964.

Genovese, a 28-year-old, was attacked and stabbed by a man later identified as Winston Moseley while on her way home from work.

Despite repeatedly calling for help, none of the people within earshot came to her rescue or reported the incident to the police.

The newspaper report of the murder stated that 38 people had heard and seen the attack, which lasted an hour, yet they did nothing.

People seemed to be displaying the bystander effect.

Subsequent reports, however, suggest the number of witnesses was much lower and few, perhaps none, had witnessed the whole attack.

Whatever the status of this incident the facts of the subsequent bystander effect study are well-known.

The bystander effect experiment

Participants were invited into the lab under the pretext they were taking part in a discussion about ‘personal problems’ ( Darley & Latane, 1968 ).

Participants in the bystander effect experiment were talking to a number of unknown others, varying from just one up to four in each of the experimental trials.

Because of the sensitive nature of the discussion they were told the discussion would take place over an intercom.

In fact this was just a ruse to ensure the participants couldn’t physically see the other people they were talking to and ruin this test of the bystander effect.

During the discussion one member of the group would suddenly appear to be having an epileptic seizure.

Here is the script:

“I-er-um-I think I-I need-er-if-if could-er-er-somebody er-er-er-er-er-er-er give me a little-er-give me a little help here because-er-I-er-I’m-er-erh-h-having a-a-a real problem-er-right now and I-er-if somebody could help me out it would-it would-er-er s-s-sure be-sure be good . . . because-there-er-er-a cause I-er-I-uh-I’ve got a-a one of the-er-sei er-er-things coming on and-and-and I could really-er-use some help so if somebody would-er-give me a little h-help-uh-er-er-er-er-er c-could somebody-er-er-help-er-uh-uh-uh (choking sounds). . . . I’m gonna die-er-er-I’m . . . gonna die-er-help-er-er-seizure-er-[chokes, then quiet].”

The experimenters then measured how long it took for participants to go the person’s aid.

Results: bystander apathy

The results of the bystander effect experiment clearly showed that the more people were involved in the group discussion, the slower participants were to respond to the apparent emergency.

It seems that the presence of others inhibits people’s helping behaviours.

Some participants made no move to intervene in the apparent emergency — they displayed bystander apathy.

What was going on?

Explanation: diffusion of responsibility

Darley and Latane (1968) report that those who did not act were far from uncaring about the seizure victim.

Quite the reverse in fact, compared to those who did report the emergency, they appeared to be in a more heightened state of arousal.

Many were sweating, had trembling hands and looked to be in considerable discomfort.

The non-helpers in the bystander effect experiment appeared to be caught in a double bind that locked them up.

One part of them felt shame and guilt for not helping.

Another part of them didn’t want to expose themselves to embarrassment or to ruin the experiment which, they had been told depended on each conversant remaining anonymous from the others.

Psychologically, what is happening in the bystander effect is that people feel less urgency the more people are present.

This diffusion of responsibility occurs because there are more people who could help.

Each person thinks to themselves that someone else will do something about it.

Then, when other bystanders do not react either, people take this as a sign that there is no need to help out.

The originality of the bystander effect

Now compare this study of the bystander effect with the Milgram experiment .

Certainly the Milgram experiment on obedience casts a long shadow over this bystander effect experiment.

Similar to the Milgram situation, participants here were put under pressure to continue with the experiment by authority figures (the psychologists).

Again, someone was suffering discomfort and participants felt conflicted about whether or not to intervene.

In this case in an epileptic seizure, in Milgram’s study, it was the electrical shocks participants themselves were administering.

This bystander effect study’s originality comes from the finding that the more people are present, the longer participants take to help.

And this is certainly an important insight in social psychological terms.

Because of the way the bystander effect experiment was set up, participants had no way of knowing how the other people who heard the seizure had responded.

This meant that the only variable was how many other people they knew to be present.

Challenging the bystander effect

Modern studies have not always supported the validity of the bystander effect in the real world.

For example, a recent study of real public fights caught on CCTV showed that bystanders intervened 90 percent of the time to help victims of violence ( Philpot et al., 2020 ).

The 219 fights included in the study had broken out on the streets of Amsterdam, Cape Town and Leicester (in the Netherlands, South Africa and UK, respectively).

Nine-out-of-ten times at least one person tried to intervene, sometimes more than one.

This strongly suggests that trying to help is the norm in public, rather than the exception as the bystander effect suggests.

Factors affecting the bystander effect

This modern study paints rather a different picture of the bystander effect than social psychological research conducted in the 1960s.

Many subsequent studies have shown that whether people will help you out in public depends on a whole range of factors, including:

• How much danger you appear to be in,
• what the costs of helping are (embarrassment, injury etc.)
• whether they are in a hurry,
• your race/ethnicity,
• what the social rule is in that situation.

→ This post is part of a series on the best social psychology experiments :

• Halo Effect : Definition And How It Affects Our Perception
• Cognitive Dissonance : How and Why We Lie to Ourselves
• Robbers Cave Experiment : How Group Conflicts Develop
• Stanford Prison Experiment : Zimbardo’s Famous Social Psychology Study
• Milgram Experiment : Explaining Obedience to Authority
• False Consensus Effect : What It Is And Why It Happens
• Social Identity Theory And The Minimal Group Paradigm
• Negotiation : 2 Psychological Strategies That Matter Most
• Asch Conformity Experiment : The Power Of Social Pressure

Author: Dr Jeremy Dean

Psychologist, Jeremy Dean, PhD is the founder and author of PsyBlog. He holds a doctorate in psychology from University College London and two other advanced degrees in psychology. He has been writing about scientific research on PsyBlog since 2004. View all posts by Dr Jeremy Dean

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Bystander Effect

The Bystander Effect: Exploring the Paradox of Human Behavior

The bystander effect, a term firmly entrenched in the lexicon of social psychology, presents a paradoxical facet of human behavior. It is a phenomenon that has intrigued scholars, psychologists, and the public alike, prompting us to question the very nature of our actions—or inactions—in the presence of others. This comprehensive examination will delve into the origins of the bystander effect. We will explore its psychological underpinnings, and unravel the complex tapestry of social, cognitive, and individual variables that influence our propensity to help those in need. As we embark on this journey, we will confront unsettling truths about social conformity and personal responsibility. Hopefully, with increased understanding we can unveil pathways leading towards a more empathetic and proactive society.

Key Definition:

The bystander effect refers to the phenomenon where individuals are less likely to offer help to a victim when other people are present. Factors such as the number of bystanders, diffusion of responsibility, and social influence contribute to this effect. When multiple bystanders are present, individuals may feel less personally responsible to take action, assuming that someone else will intervene. This can lead to inaction and a reduced likelihood of assistance in emergency situations. Research on the bystander effect has important implications for understanding social behavior and helping interventions.

The main concepts in the  bystander effect  are centered around the phenomenon where individuals are less likely to offer help to a victim when other people are present. This is a well-studied social psychological occurrence that can happen in various emergency or non-emergency situations.

Kitty Genovese and the Bystander Effect

Kitty Genovese, born Catherine Susan Genovese, was a woman whose murder in 1964 became a defining case in the study of the bystander effect in psychology.

Genovese was born on July 7, 1935, in Brooklyn, New York. She was the oldest of five children and was known to be a good student, voted “Class Cut-Up” in her senior year. After graduating from high school, she worked as a secretary and later as a bar manager in Queens, New York.

In the early hours of March 13, 1964, Genovese was returning home from work when she was attacked by Winston Moseley outside her apartment in Kew Gardens, Queens. She was stabbed, raped, and robbed. The attack lasted over half an hour, and Genovese eventually succumbed to her injuries.

The murder gained notoriety due to initial reports claiming that 38 witnesses saw or heard the attack but did nothing to intervene or call the police. This led to the study of the bystander effect, also known as “Genovese syndrome.” However, later investigations revealed that the number of witnesses was exaggerated and that some did attempt to contact authorities.

Despite inaccuracies in the original reporting, Genovese’s case had a lasting impact on social psychology and prompted the development of the 911 emergency system in the United States.

Kitty Genovese’s story is often cited in discussions about human behavior, social responsibility, and the psychological mechanisms that govern our actions in group settings.

The history of the  bystander effect  dates back to the  1960s , following the tragic murder of Genovese. Here’s a brief overview of the development of the bystander effect theory:

• 1964 : The term “bystander effect” was first proposed after the murder of Kitty Genovese in New York. Reports claimed that numerous witnesses did nothing to help, which led to public outrage and interest in understanding why people might not offer help in such situations.
• 1968 : The Genovese case motivated social psychologists  John M. Darley  and  Bibb Latané  to study the bystander effect systematically. They conducted laboratory experiments to investigate the phenomenon.
• Darley and Latané’s Experiments : They found that the presence of others significantly decreased the likelihood that any one person would help. Their work introduced key concepts like  diffusion of responsibility  and  social influence , which became central to understanding the bystander effect.
• 1970s and Beyond : Following these initial studies, further research explored various factors that influence the bystander effect, such as the number of bystanders, the ambiguity of the situation, and group cohesiveness.
• Recent Studies : More recent research has examined the bystander effect in “real world” settings, including how it manifests in workplace environments and during emergencies captured on security cameras. These studies have sometimes challenged the robustness of the effect, finding that intervention is more common than previously thought.

Darley and Latané’s Experiments

John M. Darley and Bibb Latané conducted groundbreaking experiments on the bystander effect in the late 1960s. Their research aimed to understand why people often do not help in emergency situations when others are present. Here are some of the key experiments they conducted:

• The Smoke-Filled Room Experiment : In one of their most famous studies, participants were placed in a room to fill out questionnaires. While they were working, smoke began to filter into the room through a vent. The experimenters observed whether the participants would report the smoke and how their response was affected by being alone or in the presence of others who were actually confederates instructed to ignore the smoke.
• The Seizure Experiment : Participants were asked to discuss personal problems over an intercom. During the discussion, one of the participants (a confederate) appeared to have a seizure. The real participants’ likelihood of seeking help was measured, and it was found that they were less likely to help if they believed there were other people also listening to the conversation.
• The Lady in Distress Experiment : In collaboration with Judith Rodin, another experiment involved a staged situation where a woman appeared to be injured and in need of help. The participants’ responses were observed when they were alone, with a friend, or with a stranger. It was found that 70% of the people alone called out or went to help the woman, but when paired with a stranger, only 40% offered help ( Darley & Latané, 1968 ).

These experiments demonstrated that the presence of others can significantly inhibit helping behavior, a phenomenon now known as the bystander effect. The findings from Darley and Latané’s research have had a profound impact on our understanding of social psychology and human behavior in group settings.

Key Concepts of Theory

Diffusion of responsibility.

Diffusion of responsibility is a psychological phenomenon where individuals are less likely to take action or feel responsible in a group setting because they believe that others present will act instead. This can lead to inaction or reduced help provided by bystanders in emergency situations, known as the bystander effect.

Kahneman’s Experiment

Daniel Kahneman explains, “individuals feel relieved of responsibility when they know that others have heard the same request for help.” He elaborates, “most of us think of ourselves as decent people who would rush to help in such a situation, and we expect other decent people to do the same.” Kahneman conducted an experiment of having a compatriot feign a seizure while students were rushing across campus for an exam. Many of the students passed by the person in need.

Kahneman explains that, “even normal, decent people do not rush to help when they expect others to take on the unpleasantness of dealing with a seizure.” He posits that “the presence of others would reduce my sense of responsibility…the diffusion of responsibility…induces normal and decent people…to behave in a surprisingly unhelpful way” ( Kahneman, 2013. Kindle location:  2,904 ).

In the context of the bystander effect, diffusion of responsibility occurs when multiple people witness an emergency situation but do not intervene because each individual assumes someone else will take charge. This diffusion of responsibility can result in delays in seeking help or assistance for the person in need, leading to potentially harmful outcomes. Moreover, diffusion of responsibility also”lowers inhibition of harming others” ( Zimbardo, 2007 ).

Understanding how diffusion of responsibility influences behavior during emergencies is crucial for creating interventions and strategies to encourage individuals to overcome this tendency and provide timely assistance when needed. By raising awareness about this phenomenon and promoting personal accountability among bystanders, we can work towards reducing the negative impact of diffusion of responsibility on helping behavior.

Social Influence

Social influence plays a significant role in the bystander effect, which is the phenomenon where individuals are less likely to provide help in an emergency situation when others are present. In this context, social influence refers to how the presence and actions of others can impact an individual’s decision-making and behavior.

There are two main forms of social influence that contribute to the bystander effect:

• Conformity : Bystanders may conform to the perceived norms or behaviors of those around them. If other witnesses are not offering help or taking action, individuals may be more inclined to follow suit and refrain from helping as well. This can create a sense of uncertainty and ambiguity about whether intervention is necessary or appropriate.
• Pluralistic Ignorance: This occurs when individuals look to others for cues on how to behave but mistakenly interpret their inaction as a sign that the victim does not need help. As a result, each person assumes that others must know something they don’t and refrains from taking action themselves, leading to a collective lack of response.

Belongingness and Social Influence

Philip Zimbardo explains that “other people are more likely to accept us when we agree with them than when we disagree, so we yield to their view of the world, driven by a powerful need to belong, to replace differences with similarities.” Zimbardo continues to explain that when we conform our brains are at ease, coasting in a homeostatic balance. However “if you make independent judgments that go against the group, your brain would light up in the areas that are associated with emotional salience (the right amygdala and right caudate nucleus regions). This means that resistance creates an emotional burden for those who maintain their independence—autonomy comes at a psychic cost” ( Zimbardo, 2007. Kindle location: 6,227 ).

Understanding the impact of social influence in perpetuating the bystander effect highlights the importance of promoting individual responsibility and empowering bystanders to trust their own judgment rather than relying solely on group dynamics. By raising awareness about these social influences and encouraging proactive intervention strategies, we can work towards overcoming barriers to helping behavior in emergency situations.

Evaluation Apprehension

Evaluation apprehension is a concept in social psychology that refers to the fear or concern individuals have about how they will be perceived and evaluated by others. In the context of the bystander effect, evaluation apprehension can influence an individual’s decision whether to intervene in an emergency situation when others are present.

When people are unsure of how their actions will be judged by those around them, they may hesitate to offer help for fear of making a mistake, appearing foolish, or facing criticism from others. This fear of negative evaluation can lead bystanders to prioritize social approval over taking action to assist someone in need.

In situations where multiple bystanders are present, evaluation apprehension can be heightened. The group of others may excite worry of judgement. Individuals may worry about standing out from the group. Perhaps, they may fear others seeing them as overly intrusive if they take action while others remain passive. This concern about peers judging them can contribute to diffusion of responsibility and inhibit helping behavior among bystanders.

Cognitive Dissonance

Those that standby without helping typically don’t do so in apathetic disconnection. They are torn between action and inaction. Darley and Latané observed “the emotional behavior of these nonresponding subjects was a sign of their continuing conflict, a conflict that other subjects resolved by responding.” They continue, “on the one hand, subjects worried about the guilt and shame they would feel if they did not help the person in distress, on the other hand, they were concerned not to make fools of themselves” ( Darley & Latané, 1968 ).

I experienced this during my twenty-five years as a police officer in a big city. I seen many emergency situations. Often, those actively engaged in helping often surround the victims. Ordinarily, there is a moment of freezing, perhaps an assessment or evaluation, then one person courageously steps forward to help the person in need. Once the first person steps forward then several others follow suit.

Recognizing the role of evaluation apprehension in shaping responses during emergencies underscores the importance of creating environments that support and encourage prosocial behavior while minimizing concerns about judgment or disapproval. By promoting empathy, fostering a sense of community responsibility, and reducing barriers related to social evaluation, we can help overcome the inhibiting effects of evaluation apprehension on bystander intervention.

See Self-Presentation Theory for more on this topic

Emergency vs. Non-Emergency Situations

In the context of the bystander effect, the distinction between emergency and non-emergency situations plays a crucial role in influencing bystanders’ responses and likelihood of intervening to help those in need.

• Emergency Situations : In emergency situations where there is a clear and immediate threat to someone’s health or safety, bystanders are more likely to recognize the urgency of the situation and feel compelled to take action. However, the presence of other bystanders can lead to diffusion of responsibility. This causes individuals to assume that someone else will provide assistance. This diffusion of responsibility can result in delays or even a complete lack of help being offered. This may occur despite the severity of the emergency.
• Non-Emergency Situations : In contrast, in non-emergency situations where the need for assistance may not be as apparent or urgent, bystanders may be less likely to intervene due to factors such as ambiguity about whether help is needed, social norms dictating non-involvement, or concerns about evaluation by others. The presence of multiple bystanders can further exacerbate this hesitancy to act.

Robert Sapolski argues that “the mythic elements of the Genovese case prompt the quasi myth that in an emergency requiring brave intervention, the more people present, the less likely anyone is to help—’There’s lots of people here; someone else will step forward.’ The bystander effect does occur in non-dangerous situations, where the price of stepping forward is inconvenience.” He continues, “however, in dangerous situations, the more people present, the more likely individuals are to step forward” ( Sapolski, 2018. Kindle location: 1,604 ).

Perhaps, it is like my experience suggests, all it takes is one person to break the ice . Only then does a flow of help begin from all those previously frozen in a state of dissonance.

Neuroscience and the Bystander Effect

Recent research on the bystander effect has examined the involvement of neural mechanisms leading to the phenomenon. A recent functional MRI (fMRI) study mapped neural activity as a function of the number of bystanders present. They found that when bystanders witnessed an elderly woman collapsing to the ground, and the bystander was alone or with only a few other witnesses, activity increased in the vision and attention related regions, but not in the mentalizing network. However, when the number of bystanders increased the fMRI revealed decreased activity in these regions.

Neuroscience identifies activity in the vision and attention regions as essential activation leading to help related behaviors. Research associates these regions, located in the medial prefrontal cortex (MPFC), with emotional and social processes. Scientist believes that the MPFC has an overarching role in the mapping of situation-response associations ( Hortensius & de Gelder, 2018 ).

Associated Concepts

• Social Proof : This concept suggests that individuals look to others to determine the correct behavior in ambiguous situations. It’s closely related to the bystander effect as individuals may rely on the group’s reaction (or lack thereof) to gauge whether intervention is necessary.
• Conformity : This refers to the act of matching attitudes, beliefs, and behaviors to group norms. In the context of the bystander effect, individuals may conform to the group’s inaction. This may occur even when an individual personally believe sthey should help.
• Deindividuation : This is a state where individuals in a group lose self-awareness and feel less accountable for their actions. This can lead to a decreased likelihood of helping behavior in group settings.
• Pluralistic Ignorance : This occurs when individuals mistakenly believe that their own thoughts, feelings, or behaviors are different from those of the group. In emergency situations, if no one takes action, each bystander may incorrectly assume that others do not perceive the situation as an emergency. Paradoxically, everyone may want to help, yet because of this phenomenon, no one does.

Traits that Contribute to Helping

• Altruistic Behaviors : Altruistic behavior in the context of the bystander effect refers to the selfless act of helping others without expecting any reward or benefit in return. It’s a form of prosocial behavior that various factors, including the presence of other people influence.
• Human Kindness : Human kindness is an underlying pattern of behaviors geared towards helping others. Kind individuals will offer help in the face of other factors motivating hesitancy. We need more kindness.
• Empathy : In the context of the bystander effect, empathy plays a significant role in influencing whether an individual will offer help to someone in need when other people are present. Empathy involves the ability to understand and share the feelings of another person. Empathy can motivate prosocial behavior, such as intervening in an emergency situation

The bystander effect is a complex phenomenon that involves various psychological and social factors. Associated concepts or similar concepts include:

A Few Words by Psychology Fanatic

In conclusion, the bystander effect is a multifaceted psychological phenomenon that reveals the complexities of human behavior in group settings. It underscores the tension between individual moral imperatives and the social dynamics that can inhibit action. While a tragic event initially provided the impetus for studying this effect, the ensuing research has provided invaluable insights. Accordingly, the research uncovered factors that encourage or deter prosocial behavior.

Understanding the bystander effect is more than an academic pursuit; it is a critical step towards fostering a society where empathy, responsibility, and kindness prevail over apathy and inaction. By educating individuals about the psychological barriers to helping others and promoting awareness of the power of personal intervention, we can hope to inspire more altruistic actions in critical moments. Understanding often promotes growth.

As we continue to explore this social phenomenon, let us not only be mindful of the conditions that may prevent us from acting but also celebrate the instances of courage and compassion that defy these odds. With empathy and kindness, we can help in the face of our fears. The bystander effect does not have to be an inevitable aspect of human nature. With conscious effort and understanding, we can all become the helping hand that turns a bystander into a lifeline.

Last Update: June 15, 2024

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References:

Darley, John & Latane, Bibb ( 1968 ). Bystander Intervention in Emergencies: Diffusion of Responsibility. Journal of Personality and Social Psychology, 8(4), 377-383. DOI: 10.1037%2Fh0025589

Hortensius, R., & de Gelder, B. ( 2018 ). From Empathy to Apathy: The Bystander Effect Revisited. Current Directions in Psychological Science, 27(4), 249–256. DOI: 10.1177/0963721417749653

Kahneman, Daniel ( 2013 ). Thinking Fast; Thinking Slow. Farrar, Straus and Giroux; 1st edition.

Sapolski, Robert ( 2018 ). Behave: The Biology of Humans at Our Best and Worst. Penguin Books; Illustrated edition.

Zimbardo, Philip ( 2007 ). The Lucifer Effect: Understanding How Good People Turn Evil. ‎Random House; 1st edition.

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Why People Stand By: A Comprehensive Study About the Bystander Effect

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The Bystander Effect (Definition + Examples)

Anyone who has been through high school or college knows that group projects are the worst. It always seems like no one is pulling their weight and someone has to step up and put most of the work on their shoulders. 

Why does that always happen? 

Psychologists might say that it has something to do with The Bystander Effect. But the Bystander Effect isn’t just a phenomenon that happens in the college classroom. It happens in cities, crowds - and even crime scenes. 

What Is the Bystander Effect? 

The Bystander Effect is the idea that as a bystander, you are less likely to intervene or take action when you are surrounded by others. People are less likely to provide assistance to another person if they feel that they are in the presence of a crowd.

Where Did the Bystander Effect Come From? 

The Bystander Effect has been a subject of studies since the 1960s. Many psychologists believe that research on the Bystander Effect started with the murder of Kitty Genovese.

Genovese was murdered outside of her apartment at 3 a.m. in 1964. Two weeks later, the New York Times published an article titled “37 Who Saw Murder Didn't Call the Police.” The headline shocked the world. How could 37 people fail to take action when something so horrific was happening? Did this mean cities like New York were extra dangerous? Do people not have compassion? 

These are some of the questions that psychologists have been trying to answer since the 1960s. 

Diffusion of Responsibility 

How do people explain their inaction? In the case of Kitty Genovese, media sources said that witnesses just “didn’t want to get involved.” But social psychologists have a more scientific way to explain why The Bystander Effect occurs. 

Attribution is the study of how people explain causes and effects. The Diffusion of Responsibility is a form of attribution that is often used to explain “bystander apathy.” When people are in a large group, responsibility to take action is diffused throughout the entire group. This reduces each individual’s responsibility and decreases their motivation to act. 

For example, if you are the only person witnessing a robbery, you are the only person who has a responsibility to stop the crime or report it to the police. If you are in a crowd and witness a robbery, you are one of many people who could potentially stop the crime or report it to the police. When the same responsibility is “diffused” among a larger group of people, everyone is more likely to say, “They’ll do it.” Each person may even mentally “assign” the responsibility to someone in the crowd who looks more capable or “should” take action. 

Bystander Effect Experiments Examples

Four years after the Kitty Genovese murder, two social psychologists conducted multiple studies on The Bystander Effect. John M. Darley and Bibb Latané set up different scenarios in which subjects would see or hear a possible emergency. Subjects would either be alone, with a small group of people, or with a larger group of people. The researchers would then record whether or not the subject reported the incident. 

Take their first experiment. The researchers gave the subjects a questionnaire to fill out in a room. They left the room and began to fill it with smoke. 

In one room, the subject was entirely alone. In another room, three other people sat in the room and ignored the smoke. In the last room, three other people sat in the room and two visibly noticed the smoke and ignored it. 

Here are the results. 

75% of the participants who sat in the room alone got up to report it to someone in the building. Only 38% of participants sat in the room with three people who failed to see the smoke reported the smoke. Even more shocking, 10% of the participants who sat in the room with people who acknowledged and ignored the smoke reported what they saw. 

How the Bystander Effect’s History Affects How We View It 

It’s been over 50 years since Kitty Genovese’s murder. The New York Times headline that shocked the world has since been revealed as a fraud. (While 38 people gave statements to the police about hearing something, there were not 37 eyewitnesses to Kitty’s murder. And multiple calls were made to the police regarding Kitty’s screams.) 

Bystander Effect Example: Khaseen Morris

But the research regarding The Bystander Effect still proves to be an uncomfortable look at how we distribute responsibility and excuse our inactions. Cases of The Bystander Effect continue to make headlines in newspapers and online. In September 2019, a 16-year old named Khaseen Morris was stabbed to death while in a fight outside of a strip mall. Dozens of people witnessed the teen’s death. Many even filmed the fight and broadcast it over Snapchat. But no one intervened. (Eight people are in jail over the teen’s death.) 

Brain development, cultural norms, and other factors may all play a role in why people don’t intervene when an emergency is taking place. There is more research to be done on The Bystander Effect, and sometimes attribution varies case by case. But what we do know is that stories like Kitty Genovese or Khaseen Morris shock (and often disgust) the world. Failing to take action paints a picture of a world where people naturally lack compassion and tolerate suffering. And for most people, this is not a world that they do not want to live in. 

How to Overcome the Bystander Effect 

The knowledge of the diffusion of responsibility or the Bystander Effect may help you consciously make better decisions when you witness an emergency, or just work in a group project. If you catch yourself saying that you “don’t want to get involved,” or stand around waiting for someone else to take action, remember that you are being a bystander.

Take action when you see wrongdoing. Report things before waiting for someone else to report them. Assign someone to call 911 so they know it is their  responsibility. You just might save someone’s grade in your college class - or someone’s life.

Related posts:

• The Good Samaritan Effect (Definition + Examples)
• The Kitty Genovese Murder
• False Consensus Effect (Definition + Examples)
• Hawthorne Effect (Definition + Examples)
• Lake Wobegon Effect (Definition + Examples)

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Piliavin (1969) Subway Study

Julia Russel

Head of Psychology

BSc (Hons), Psychology

Julia Russell has over 25 years experience as a Psychology teacher. She is currently Head of Psychology at The Queen’s School, Chester. She is Principal Examiner for two major awarding bodies, visiting tutor at Wrexham Glyndŵr University and an established author.

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Saul McLeod, PhD

Editor-in-Chief for Simply Psychology

BSc (Hons) Psychology, MRes, PhD, University of Manchester

Saul McLeod, PhD., is a qualified psychology teacher with over 18 years of experience in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.

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Piliavin I. M., Rodin, J., & Piliavin, J. A. (1969). Good samaritanism: an underground phenomenon?. Journal of Personality and Social Psychology, 13 (4), 289.

This study was designed to investigate how a group of people would react if they saw a person who collapsed on a train.

Specifically, they wanted to investigate the following:

• Would an ill person get more help than a drunk person? (the type of victim)?
• Would people help others of the same race before helping those of different races?
• If a model person started helping the victim, would that encourage others to also help?
• Would the number of bystanders who saw the victim influence how much help was given?

This study was a field experiment on a 7 ½ minute non-stop journey on a New York underground train, using various coaches along the train. Participants were passengers who were on board.

Using teams of 4 university students (male victim, male model, 2 female observers), a situation was created on the train to see how passengers would react.

A ‘victim’ staged an ‘emergency’ by collapsing (in the designated ‘critical area’).

After collapsing, the victim lay on his back on the floor. If not helped earlier in the journey by a participant or model, the model assisted the victim at the end of the journey.

Participants’ reactions were then watched by covert observers.

Participants

The victims were: males aged 26 -35; three white, one black; identically dressed in a US army-style jacket, old trousers, and no tie.

The ‘drunk’ smelled of alcohol and carried a spirits bottle wrapped in a brown paper bag (38 trials). The ‘ill ‘victim appeared sober and carried a black cane (65 trials).

The  models were males aged 24 – 29, wore casual but not identical clothes, and helped by raising the victim to a sitting position and staying with him.

Independent Variables

• Type of victim (drunk or appearing ill and would hold a walking cane).
• Race of victim (black or white).
• Effect of the model (a researcher in disguise): stood near the victim and helped after about 70 seconds (critical area – early), stood in the same place but helped after 150 seconds (critical area – late), or stood further away and helped quickly or slowly (‘adjacent – early’ and ‘adjacent – late’), or no model at all. The trials were determined randomly.
• Size of the witnessing group (a naturally occurring independent variable). The sample consisted of the 4450 American passengers using that particular train, 45% of which were black and 55% white.

Dependent Variables

The dependent variables were covertly recorded (from behind newspapers) by two female observers seated in the adjacent area (during 103 victim trials):

• Number of bystanders
• Frequency of witness help
• Latency (time) to help
• Race of helper (45% black, 55% white)
• Sex of helper
• Number of helpers
• Movement out of the critical area
• Any verbal comments made by bystanders

There were 6-8 trials per day, on journeys in alternating directions, all the same victim type on any day.

• Models were rarely needed; the public usually helped quickly on their own.
• Apparently, ill victims are more likely to be helped than apparently drunk ones (62/65 trials compared to 19/38) and are more likely to be helped quickly.
• Males are more likely to help than females (60% of travelers were male, but 90% of first helpers were male).
• Race has little effect on helping, although a drunk victim is less likely to receive opposite-race help.
• The longer no help is offered, the less important modeling becomes and the more likely someone is to leave the area, and more so with drunk victims.
• Spontaneous comments were more common in the drunk condition.

One of the surprising findings in this study was that there was no diffusion of responsibility. The size of the group made no difference in how much help a victim received. Piliavin et al. offered several explanations for this:

• Passengers were trapped on the train and could not really leave the situation. On the street, the results may have been different.
• It was less effort for passengers to help. If they were sitting on the train anyway and were waiting for the next stop, they may as well help.
• Unlike the situation with Kitty Genovese , it was clear what the problem was for the bystanders who were sitting next to the victim.

Piliavin et al. (1969) put forward the cost–reward arousal model as a major alternative to the decision model and state it represents a ‘fine tuning’ of the earlier model.

In a similar fashion to Latané and Darley’s decision-helping model , it has two stages that occur before we either help or don’t help.

The first stage is physiological arousal. Arousal in response to the need or distress of others is an emotional response and provides the basic motivational construct of the model.

When we see someone in distress, we become physiologically aroused. The greater the arousal in emergencies, the more likely it is that a bystander will help since they wish to reduce it.

The cost–reward component stage involves evaluating the consequences of helping or not helping. Whether one helps or not depends on the outcome of weighing up both the costs and rewards of helping.

The costs of helping include effort, time, loss of resources, risk of harm, and negative emotional response. The rewards of helping include fame, gratitude from the victim and relatives, and self-satisfaction derived from the act of helping.

The costs of not helping include guilt, disapproval, damaged self-esteem, and also negative emotional responses. It is recognized that costs may be different for different people and may even differ from one occasion to another for the same person.

Helping is more likely: with ill than drunk victims; to be offered by males (as perceived costs are higher and social role reduces self-blame), and with same-race victims if they appear drunk (as perceived risk is higher, social role reduces self-blame and there may be same-race empathy and trust).

The longer an emergency continues, the less important the role of a model (because arousal has been reduced by other means) and the more likely people are to leave the area.

Critical Evaluation

The data gathered was both qualitative and quantitative . The quantitative data included the number and type of passengers who helped as well as the time taken to offer assistance.

The qualitative data came from the spontaneous comments made by the passengers. Both types of data are valuable in building up a full picture of what happened and why.

The quantitative data allowed for comparisons and statistical analysis, and the qualitative data provided some of the thoughts and feelings of the people involved, including perhaps providing explanations for why they did or did not help.

Reliability refers to the consistency of a measure and one aspect of reliability relevant to studies involving observations is how consistent different observers are when recording information on the same event, i.e., inter-rater reliability.

The reliability of this study was increased by the fact that there were two independent researchers observing and recording data. Hence they were able to measure inter-rater reliability.

Some people argue that the cost–reward arousal model is overly calculating. We do not weigh up the pros and cons of helping in as much detail as they suggest. Whilst arousal and helping are often only correlated, the model clearly sees the former as causing the latter.

According to Dovidio et al. (1991), evidence indicates that emotional reactions to other people’s distress play an important role in motivating helping. The model proposes that bystanders will choose the response that most rapidly and completely reduces the arousal, incurring as few costs as possible.

Therefore the emotional component provides the motivation to do something, whilst the cognitive component determines what the most effective response will be.

Piliavin et al.’s original model was subsequently elaborated to take account of the role played by other factors.

Many of the variables interact and contribute to how aroused the bystander is and the perceived costs and rewards for direct intervention.

A strength of the sample is that it is fairly big and, therefore, would be representative of people who used the subway in NYC; e.g., 4450 participants were estimated to have been involved.

One ethical issue is the lack of informed consent within this study – participants were not aware that they were involved in an experiment.

Another ethical issue in Piliavin et al.’s study is that the participants could not be debriefed at the end of the experiment.

Thus, not allowing the participants to know that they were involved in an experiment and that all incidences that occurred on that Subway journey were controlled.

Dovidio, J. F., Piliavin, J. A., Gaertner, S. L., Schroeder, D. A., & Clark III, R. D. (1991). The arousal: Cost-reward model and the process of intervention: A review of the evidence.

Piliavin, I. M., Rodin, J., & Piliavin, J. A. (1969). Good samaritanism: an underground phenomenon ?  Journal of Personality and Social Psychology, 13 (4), 289.

AP® Psychology

Who were latane and darley ap® psychology bystander effect review.

• The Albert Team
• Last Updated On: March 1, 2022

Introduction to Who were Latane and Darley

If you witnessed an emergency, you would certainly help those in need, right? Even if you didn’t directly address the problem, if someone were in desperate need of help, you would definitely call the police or an ambulance at the very least, correct? Well, social psychology doesn’t think so. Based on Latane and Darley’s experiments on the bystander effect, your likelihood of helping a person in an emergency is highly dependent on the number of people around you at that moment. The bystander effect is an important social behavior from which we can learn a lot for periods of crisis, and it helps us understand human behavior for groups of people. Therefore, it is important to understand the bystander effect, its causes and possible counteractions for the Advanced Placement (AP) Psychology exam.

Would You Help Kitty Genovese?

New York, March 13, 1964. A woman named Catherine Susan Genovese, commonly known as Kitty Genovese, is stabbed, robbed, sexually assaulted and murdered on the street by a man named Winston Moseley. The tragedy lasted for approximately thirty minutes, during which Kitty Genovese screamed for help. The lights on the nearby apartments went on and off, neighbors heard her screaming, watched from the windows and not one of the thirty-eight witnesses called the police.

If this were a scene from a thriller book, it would sound non-realistic. The editor of the book would probably look straight at the author and protest, “You can’t put a bunch of witnesses on a thirty-minute crime and have none of them lift a finger to help! No reader would believe this!”

This is why the murder of Kitty Genovese shocked the population in 1964. We like to think we are mostly good, ethical and altruistic individuals who would never refuse to help someone in an emergency. At the time, professors and preachers tried to explain this apparently horrifying indifference and lack of intervention with reasons such as “moral decay,” “alienation” and “dehumanization produced by the urban environment.” Social psychology researchers Bibb Latane and John Darley , however, had another hypothesis.

Their hypothesis was that when we are in the presence of other people, we are less likely to intervene in an emergency. Why? What happens? What’s so different between being alone and being in a group when a problem occurs? This is what Latane and Darley explored in their experiments on bystander effect, a critical discovery in the field of social psychology .

The Experiments

In 1968, Latane and Darley created a situation similar to that of Kitty Genovese’s (but without violence)to understand what social forces were acting on the day of the crime.

In the first experiment, Latane and Darley recruited college students to participate in what seemed to be an innocent talk with other college students. Each participant was given headphones and a microphone and stayed alone in a room, talking to other students through the intercom. According to the researchers, this was done to protect everyone’s anonymity. The theme of the conversation was college life problems, worries and the like.

Next, Latane and Darley divided the participants into three groups:

• The first group thought they were talking one on one with the other person
• The second group thought they were talking with two other people
• The third group thought they were talking in a group of five people

In a certain point of the conversation, a person in the intercom started acting as if he was having a seizure and asked for help. Latane and Darley wanted to investigate the difference of behavior between each group, according to the number of witnesses. These were the results:

• When participants thought they were the only ones who could help, 85% of them left the room and asked for assistance
• When participants thought there were other two bystanders with them, that number dropped to 64%
• In the situation with four bystanders, only 31% of participants searched for help

“Well, okay,” you might say, “Maybe the number of people around you influences the likelihood of giving assistance, but if it were the participants’ own lives that were at risk, I’m sure everybody would do something regardless of the number of bystanders.”

Latane and Darley thought about that too and developed a second experiment to investigate this. How do you think that one went down?

For the second experiment, Latane and Darley once again recruited college students, this time to “fill out a questionnaire.” They divided the participants into two groups:

• Participants filling out the questionnaire alone in a room
• Participants filling out the questionnaire with many confederates in the room who were also filling out the questionnaire

A few minutes after the participants start the task, a black smoke starts to creep out from the room’s air conditioner. It gets thicker and thicker until the room is filled with smoke. However, in the second group, the confederates were instructed to ignore the smoke, and so no one seems to be bothered about it. What do you think happened?

• Of the participants who were alone, 75% quickly left the room and reported the smoke to the researchers
• Of those who were in the room with the unshaken confederates, only 10% left the room and searched for help, after twice the time of the participants who were alone

This is a surprising result that confirms the first study’s findings: the greater the number of bystanders, the less likely we are to act. Even if we ourselves could be in danger, being surrounded by people who do nothing makes us more likely also to do nothing. This opposes the intuitive idea that the more people there are in an emergency situation, the more likely it is that someone would call for help. As Latane and Darley have shown in their studies, it is quite the contrary.

Why the Bystander Effect Happens

As we have seen earlier, the bystander effect states that the likelihood of intervention is inversely related to the number of bystanders . In other words, the more witnesses there are, the less likely each one of them is to intervene in a problematic situation. But why does this happen? What can explain this?

The main reason proposed by Latane and Darley is diffused responsibility. When you are in a large group and something needs to be done, you feel less responsible for the task. There are so many people around; someone else is surely taking charge of the situation, so why should you step up? The sense of responsibility is diffused in the group, and the result is that, very frequently, no one does anything.

This is what happened in the Kitty Genovese situation. The thirty-eight neighbors witnessed the crime and saw each other through the windows. “Of course someone will call the police,” each one of them thought, “a woman is being murdered right on the street!” Unfortunately, diffused responsibility led to none of them taking action.

Another reason for the bystander effect pointed out by Latane and Darley is pluralistic ignorance . Pluralistic ignorance is what happens when you observe a situation and at first think that, for example, it is dangerous. However, people around act as if it isn’t a problem and don’t look concerned. Then, you also assume that it’s really not a big deal and that the right thing to do is just to keep doing what you’re doing and not intervene.

In the Kitty Genovese situation, the neighbors looked around to check how others were reacting, and since no one was getting desperate and fighting to help her (because of the diffused responsibility effect), they continued with their everyday lives despite her persistent cries for help.

How the Bystander Effect Happens

According to Latane and Darley, bystanders go through a 5-step cognitive and behavioral process in emergency situations:

• Notice that something is happening – many things influence our ability to notice a situation, for example, being in a hurry or being in a group in which no one notices the event.
• Interpret the situation as an emergency – this is where the pluralistic ignorance becomes a problem, especially in ambiguous situations when people aren’t quite sure of what is happening and therefore don’t act in an urgent manner.
• Assume a degree of responsibility – this is affected by the diffused responsibility phenomenon and also by other elements such as whether we see the victim as someone deserving of help, whether we see ourselves as someone capable of helping and the relationship between the victim and ourselves.
• Choose a form of assistance – this can be a direct intervention helping the victim or a detour intervention like calling the police.
• Take action – performing the assistance chosen.

Other Variables that Influence Our Likelihood to Help

Latane and Darley’s crucial studies were further investigated by other social psychologists who continued to develop the knowledge on what makes us more likely to help others and show altruistic behavior. Some of the other variables are:

• Similarity: we are more likely to help those who are in some way similar to ourselves. This can be regarding gender, ethnicity, clothes, beliefs and even the basketball team the victim happens to root for.
• Consequences: when we think there will be strong consequences for our intervention, we are less likely to act. For example, many people avoid intervening in emergency medical situations because they are afraid of giving inadequate assistance, making the situation worse and later being held responsible for it.
• Familiarity with the environment: we are more likely to intervene in situations in places we are familiar with. That can be because, for instance, we know where the emergency exits are or where to find help quickly.

How to Counter the Bystander Effect

Okay, so now you know the dangers of the bystander effect and why and how it happens. You might be wondering: “Is there anything we can do to avoid it? How can we increase the likelihood of helping other people?”

Fortunately, there are possible measures to counter the bystander effect and avoid future Kitty Genovese situations. After all, this is the main reason to study human behavior: not to think of our tendencies in a conformed and cynical way and make the same mistakes over and over again, but to reflect on how we can improve ourselves, our lives and our relationships. So here are a few tips to use this knowledge in our service:

• Recognize situations where the bystander effect may be present and be aware of them. Realize that we are all bystanders. By doing so, next time there is a problem you’ll be able to notice it, interpret it as an emergency and assume responsibility more clearly.
• Review your concepts about who deserves help. This can get tricky when people perceive the victim as someone who brought their unfortunate events upon themselves, like drug or alcohol addicts. No one is forced to offer assistance to everybody in need, but be aware of your own ideas and tendencies.
• Know how to help people in different situations. Seeing yourself as more qualified to give assistance raises the likelihood of that behavior.
• If you need help, choose a specific person to ask for it. This avoids the diffused responsibility phenomenon. Instead of saying “Someone call an ambulance,” point directly to someone and say “You, call an ambulance!”
• If someone needs help, be the one to take action. Once people see that somebody is intervening, they are more likely to start offering assistance as well.

A Free Response Question (FRQ) Example

Now that you’ve learned all about Latane and Darley’s bystander effect, try to answer the following FRQ from a past exam:

For each of the following pairs of terms, explain how the placement or location of the first influences the process indicated by the second:

– Presence of other, performance

There are many possible answers to this question, for example social facilitation, social loafing, conformity and the theme of this AP® Psychology review : the bystander effect. Whatever you choose, the important thing is to correctly describe the phenomenon of choice and connect the elements “presence of other” and “performance” in a clear way.

So what do you think about the bystander and the diffused responsibility effect? Have you ever been in a situation where you saw Latane and Darley’s principles in action? Share in the comments below!

Let’s put everything into practice. Try this AP® Psychology practice question:

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The ‘bystander effect’ is real – but research shows that when more people witness violence, it’s more likely someone will step up and intervene

Professor, Department of Supply Chain Management, Rutgers University

Disclosure statement

Wayne Eastman does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

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The most powerful evidence for the prosecution at the trial of Derek Chauvin was a video showing the then-Minneapolis police officer pinning a pleading George Floyd to the ground by kneeling on his neck until he grew silent and then died.

On the witness stand, the teenager who captured the incident on her smartphone, 17-year-old Darnella Frazier, expressed regret for not doing more on the day of the crime.

As a professor whose major field of research is the application of psychology and game theory to ethics , I believe that Frazier’s regret about not physically intervening illuminates two major points: First, a witness to a troubling situation who is in a group may feel a lesser sense of personal responsibility than a single individual. Second, someone in a group of people who can see one another may nonetheless feel responsible to act.

The bystander effect

The sense of diminished personal responsibility for people in a group has become known as the “ bystander effect ” – a phenomenon first described in the wake of a celebrated, infamous case.

In a 1964 front-page story headlined “37 Who Saw Murder Didn’t Call the Police; Apathy at Stabbing of Queens Woman Shocks Inspector,” The New York Times related the gruesome story of the middle-of-the-night sexual assault and murder of Kitty Genovese, a 28-year-old bartender, near her apartment building.

In recent years, academics and The New York Times itself have concluded that the report had significant errors – the number of witnesses was fewer than 37 and multiple people phoned the police.

Reflecting on the notorious case long before these errors were known, social psychologists Bibb Latane and John Darley wondered if it would be possible to study failure of bystanders to act in lab experiments.

In a 1970 book , Darley and Latane summarized that the chances of any one individual acting in a pro-social or helpful way is lower when responsibility is diffused among a number of people. Subsequent studies also confirmed that individuals are more likely to act when they feel they have the sole responsibility to do so.

The bystander effect has been reformulated by game theorists as the “ volunteer’s dilemma .” In the volunteer’s dilemma, a person, or a group of people, will avoid discomfort if any one of them takes a pro-social action with a small cost, such as performing first aid or fixing a clogged drain .

Any one individual acting alone has good reason to take action – but if there is a crowd of, say, 20 people, the chance that they will do nothing and let someone else volunteer goes up .

In the case of George Floyd, the bystander effect was complicated by the power dynamics at play. Chauvin was an armed white police officer, and Frazier and the other bystanders were unarmed civilians who were mostly Black, like George Floyd himself. Given that, it is reasonable to ask whether Frazier, if she had been the sole civilian witness, would have gone beyond recording a video to physically intervene – such as trying to pull Chauvin off Floyd.

And it is also reasonable to ask whether she or any bystander should physically intervene in a situation where doing so might be extremely risky.

What makes people act

What needs to be explained in Frazier’s behavior – and that of a number of other witnesses who also recorded videos or called out to Chauvin to stop – is not why they didn’t take drastic, risky physical action, but why they did take the steps to record videos and yell for Chauvin to stop.

To explain their pro-social action, an advancing line of research on the behavior of witnesses to troubling scenes is helpful. That research suggests that having more witnesses increases rather than decreases the chance of intervention and that pro-social intervention by at least some in a group is the norm.

A 2008 analysis by social psychologist Daniel Stalder of previous studies found that although the bystander effect is real, larger group size increased the probability that at least one person in the group would make a pro-social intervention.

More recently, a 2019 article by psychologist Richard Philpot and four co-authors found that there is a greater chance that someone will act when there are larger numbers of witnesses to public conflicts. They also found that intervention is the norm : 90.7% of public conflicts featured one or more witnesses making a pro-social intervention, with an average of 3.8 witnesses intervening in each conflict.

Compared with earlier research, their study is particularly persuasive, as it relied not on lab studies, but on examining surveillance camera footage of actual public conflicts between civilians (not between police and civilians) taking place in crowded urban street settings. The research was conducted in three countries – South Africa, the Netherlands and the United Kingdom .

As Philpot and his co-authors put it , in a line that presages what Frazier and several others near her did: “We found that in nine-out-of-10 conflicts, at least one person – but typically several – did something to help.”

In trying to understand bystander ethics, the troubling phenomenon of diffusion of responsibility remains relevant. But it is also important to understand the more positive finding that pro-social intervention like Frazier’s by one or more people in groups who witness public conflicts is common.

This article was originally published in 2021.

• Volunteering
• Game theory
• Bystander effect
• Police violence
• Ethical question
• Bystander programs
• Religion and society
• George Floyd
• Derek Chauvin

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We Are All Bystanders

For more than 40 years, Peggy Kirihara has felt guilty about Stewart.

Peggy liked Stewart. They went to high school together. Their fathers were friends, both farmers in California’s Central Valley, and Peggy would always say “hi” when she passed Stewart in the hall.

Yet every day when Stewart boarded their school bus, a couple of boys would tease him mercilessly. And every day, Peggy would just sit in her seat, silent.

“I was dying inside for him,” she said. “There were enough of us on the bus who were feeling awful—we could have done something. But none of us said anything.”

Peggy still can’t explain why she didn’t stick up for Stewart. She had known his tormenters since they were all little kids, and she didn’t find them threatening. She thinks if she had spoken up on his behalf, other kids might have chimed in to make the teasing stop.

But perhaps most surprising—and distressing—to Peggy is that she considers herself an assertive and moral person, yet those convictions aren’t backed up by her conduct on the bus.

“I think I would say something now, but I don’t know for sure,” she said. “Maybe if I saw someone being beaten up and killed, I’d just stand there. That still worries me.”

Many of us share Peggy’s concern. We’ve all found ourselves in similar situations: the times we’ve seen someone harassed on the street and didn’t intervene; when we’ve driven past a car stranded by the side of the road, assuming another driver would pull over to help; even when we’ve noticed litter on the sidewalk and left it for someone else to pick up. We witness a problem, consider some kind of positive action, then respond by doing… nothing. Something holds us back. We remain bystanders.

Why don’t we help in these situations? Why do we sometimes put our moral instincts in shackles? These are questions that haunt all of us, and they apply well beyond the fleeting scenarios described above. Every day we serve as bystanders to the world around us—not just to people in need on the street but to larger social, political, and environmental problems that concern us, but which we feel powerless to address on our own. Indeed, the bystander phenomenon pervades the history of the past century.

“The bystander is a modern archetype, from the Holocaust to the genocide in Rwanda to the current environmental crisis,” says Charles Garfield , a clinical professor of psychology at the University of California, San Francisco, School of Medicine who is writing a book about the psychological differences between bystanders and people who display “moral courage.”

“Why,” asked Garfield, “do some people respond to these crises while others don’t?”

In the shadow of these crises, researchers have spent the past few decades trying to answer Garfield’s question. Their findings reveal a valuable story about human nature: Often, only subtle differences separate the bystanders from the morally courageous people of the world. Most of us, it seems, have the potential to fall into either category. It is the slight, seemingly insignificant details in a situation that can push us one way or the other.

Researchers have identified some of the invisible forces that restrain us from acting on our own moral instincts while also suggesting how we might fight back against these unseen inhibitors of altruism. Taken together, these results offer a scientific understanding for what spurs us to everyday altruism and lifetimes of activism, and what induces us to remain bystanders.

Altruistic inertia

Among the most infamous bystanders are 38 people in Queens, New York, who in 1964 witnessed the murder of one of their neighbors, a young woman named Kitty Genovese ( see sidebar ).

A serial killer attacked and stabbed Genovese late one night outside her apartment house, and these 38 neighbors later admitted to hearing her screams; at least three said they saw part of the attack take place. Yet no one intervened.

While the Genovese murder shocked the American public, it also moved several social psychologists to try to understand the behavior of people like Genovese’s neighbors.

One of those psychologists was John Darley , who was living in New York at the time. Ten days after the Genovese murder, Darley had lunch with another psychologist, Bibb Latané , and they discussed the incident.

“The newspaper explanations were focusing on the appalling personalities of those who saw the murder but didn’t intervene, saying they had been dehumanized by living in an urban environment,” said Darley, now a professor at Princeton University . “We wanted to see if we could explain the incident by drawing on the social psychological principles that we knew.”

A main goal of their research was to determine whether the presence of other people inhibits someone from intervening in an emergency, as had seemed to be the case in the Genovese murder. In one of their studies, college students sat in a cubicle and were instructed to talk with fellow students through an intercom. They were told that they would be speaking with one, two, or five other students, and only one person could use the intercom at a time.

There was actually only one other person in the study—a confederate (someone working with the researchers). Early in the study, the confederate mentioned that he sometimes suffered from seizures. The next time he spoke, he became increasingly loud and incoherent; he pretended to choke and gasp. Before falling silent, he stammered:

If someone could help me out it would it would er er s-s-sure be sure be good… because er there er er a cause I er I uh I’ve got a a one of the er sei-er-er things coming on and and and I could really er use some help… I’m gonna die er er I’m gonna die er help er er seizure er…

Eighty-five percent of the participants who were in the two-person situation, and hence believed they were the only witness to the victim’s seizure, left their cubicles to help. In contrast, only 62 percent of the participants who were in the three-person situation and 31 percent of the participants in the six-person situation tried to help.

Darley and Latané attributed their results to a “diffusion of responsibility”: When study participants thought there were other witnesses to the emergency, they felt less personal responsibility to intervene. Similarly, the witnesses of the Kitty Genovese murder may have seen other apartment lights go on, or seen each other in the windows, and assumed someone else would help. The end result is altruistic inertia. Other researchers have also suggested the effects of a “confusion of responsibility,” where bystanders fail to help someone in distress because they don’t want to be mistaken for the cause of that distress.

Darley and Latané also suspected that bystanders don’t intervene in an emergency because they’re misled by the reactions of the people around them. To test this hypothesis, they ran an experiment in which they asked participants to fill out questionnaires in a laboratory room. After the participants had gotten to work, smoke filtered into the room—a clear signal of danger.

When participants were alone, 75 percent of them left the room and reported the smoke to the experimenter. With three participants in the room, only 38 percent left to report the smoke. And quite remarkably, when a participant was joined by two confederates instructed not to show any concern, only 10 percent of the participants reported the smoke to the experimenter.

The passive bystanders in this study succumbed to what’s known as “pluralistic ignorance”—the tendency to mistake one another’s calm demeanor as a sign that no emergency is actually taking place. There are strong social norms that reinforce pluralistic ignorance. It is somewhat embarrassing, after all, to be the one who loses his cool when no danger actually exists. Such an effect was likely acting on the people who witnessed the Kitty Genovese incident; indeed, many said they didn’t realize what was going on beneath their windows and assumed it was a lover’s quarrel. That interpretation was reinforced by the fact that no one else was responding, either.

A few years later, Darley ran a study with psychologist Daniel Batson that had seminary students at Princeton walk across campus to give a talk. Along the way, the students passed a study confederate, slumped over and groaning in a passageway. Their response depended largely on a single variable: whether or not they were late. Only 10 percent of the students stopped to help when they were in a hurry; more than six times as many helped when they had plenty of time before their talk.

Lateness, the presence of other people—these are some of the factors that can turn us all into bystanders in an emergency. Yet another important factor is the characteristics of the victim. Research has shown that people are more likely to help those they perceive to be similar to them, including others from their own racial or ethnic groups. In general, women tend to receive more help than men. But this varies according to appearance: More attractive and femininely dressed women tend to receive more help from passersby, perhaps because they fit the gender stereotype of the vulnerable female.

We don’t like to discover that our propensity for altruism can depend on prejudice or the details of a particular situation—details that seem beyond our control. But these scientific findings force us to consider how we’d perform under pressure; they reveal that Kitty Genovese’s neighbors might have been just like us. Even more frightening, it becomes easier to understand how good people in Rwanda or Nazi Germany remained silent against the horrors around them. Afraid, confused, coerced, or willfully unaware, they could convince themselves that it wasn’t their responsibility to intervene.

But still, some did assume this responsibility, and this is the other half of the bystander story. Some researchers refer to the “active bystander,” that person who witnesses an emergency, recognizes it as such, and takes it upon herself to do something about it.

Who are these people? Are they inspired to action because they receive strong cues within a situation, indicating it’s an emergency? Or is there a particular set of characteristics—a personality type—that makes some people more likely to be active bystanders while others remain passive?

Why people help

A leader in the study of the differences between active and passive bystanders is psychologist Ervin Staub , whose research interests were shaped by his experiences as a young Jewish child in Hungary during World War II.

“I was to be killed in the Holocaust,” he said. “And there were important bystanders in my life who showed me that people don’t have to be passive in the face of evil.” One of these people was his family’s maid, Maria, a Christian woman who risked her life to shelter Staub and his sister while 75 percent of Hungary’s 600,000 Jews were killed by the Nazis.

Staub has tried to understand what motivates the Marias of the world. Some of his research has put a spin on the experimental studies pioneered by Darley and Latané, exploring what makes people more likely to intervene rather than serve as passive bystanders.

In one experiment, a study participant and a confederate were placed in a room together, instructed to work on a joint task. Soon afterwards, they heard a crash and cries of distress. When the confederate dismissed the sounds—saying something like, “That sounds like a tape. .. Or I guess it could be part of another experiment.”—only 25 percent of the participants went into the next room to try to help. But when the confederate said, “That sounds bad. Maybe we should do something,” 66 percent of the participants took action. And when the confederate added that participants should go into the next room to check out the sounds, every single one of them tried to help.

In another study, Staub found that kindergarten and first grade children were actually more likely to respond to sounds of distress from an adjoining room when they were placed in pairs rather than alone. That seemed to be the case because, unlike the adults in Darley and Latané’s studies, the young children talked openly about their fears and concerns, and together tried to help.

These findings suggest the positive influence we can exert as bystanders. Just as passive bystanders reinforce a sense that nothing is wrong in a situation, the active bystander can, in fact, get people to focus on a problem and motivate them to take action.

John Darley has also identified actions a victim can take to get others to help him. One is to make his need clear—“I’ve twisted my ankle and I can’t walk; I need help”—and the other is to select a specific person for help—“You there, can you help me?” By doing this, the victim overcomes the two biggest obstacles to intervention. He prevents people from concluding there is no real emergency (thereby eliminating the effect of pluralistic ignorance), and prevents them from thinking that someone else will help (thereby overcoming diffusion of responsibility).

But Staub has tried to take this research one step further. He has developed a questionnaire meant to identify people with a predisposition toward becoming active bystanders. People who score well on this survey express a heightened concern for the welfare of others, greater feelings of social responsibility, and a commitment to moral values—and they also prove more likely to help others when an opportunity arises.

Similar research has been conducted by sociologist Samuel Oliner . Like Staub, Oliner is a Holocaust survivor whose work has been inspired by the people who helped him escape the Nazis. With his wife Pearl , a professor of education, he conducted an extensive study into “the altruistic personality,” interviewing more than 400 people who rescued Jews during the Holocaust, as well as more than 100 nonrescuers and Holocaust survivors alike. In their book The Altruistic Personality , the Oliners explain that rescuers shared some deep personality traits, which they described as their “capacity for extensive relationships—their stronger sense of attachment to others and their feelings of responsibility for the welfare of others.” They also found that these tendencies had been instilled in many rescuers from the time they were young children, often stemming from parents who displayed more tolerance, care, and empathy toward their children and toward people different from themselves.

“I would claim there is a predisposition in some people to help whenever the opportunity arises,” said Oliner, who contrasts this group to bystanders. “A bystander is less concerned with the outside world, beyond his own immediate community. A bystander might be less tolerant of differences, thinking ‘Why should I get involved? These are not my people. Maybe they deserve it?’ They don’t see helping as a choice. But rescuers see tragedy and feel no choice but to get involved. How could they stand by and let another person perish?”

Kristen Monroe , a political scientist at the University of California, Irvine , has reached a similar conclusion from her own set of interviews with various kinds of altruists. In her book The Heart of Altruism , she writes of the “altruistic perspective,” a common perception among altruists “that they are strongly linked to others through a shared humanity.”

But Monroe cautions that differences are often not so clear cut between bystanders, perpetrators, and altruists.

“We know that perpetrators can be rescuers and some rescuers I’ve interviewed have killed people,” she said. “It’s hard to see someone as one or the other because they cross categories. Academics like to think in categories. But the truth is that it’s not so easy.”

Indeed, much of the bystander research suggests that one’s personality only determines so much. To offer the right kind of help, one also needs the relevant skills or knowledge demanded by a particular situation.

As an example, John Darley referred to his study in which smoke was pumped into a room to see whether people would react to that sign of danger. One of the participants in this study had been in the Navy, where his ship had once caught on fire. So when this man saw the smoke, said Darley, “He got the hell out and did something, because of his past experiences.” There’s an encouraging implication of these findings: If given the proper tools and primed to respond positively in a crisis, most of us have the ability to transcend our identities as bystanders.

“I think that altruism, caring, social responsibility is not only doable, it’s teachable,” said Oliner.

And in recent years, there have been many efforts to translate research like Oliner’s into programs that encourage more people to avoid the traps of becoming a bystander.

Anti-bystander education

Ervin Staub has been at the fore of this anti-bystander education. In the 1990s, in the wake of the Rodney King beating, he worked with California’s Department of Justice to develop a training program for police officers. The goal of the program was to teach officers how they could intervene when they feared a fellow officer was about to use too much force.

“The police have a conception, as part of their culture, that the way you police a fellow officer is to support whatever they’re doing, and that can lead to tragedy, both for the citizens and the police themselves,” said Staub. “So here the notion was to make police officers positive active bystanders, getting them engaged early enough so that they didn’t have to confront their fellow officer.”

More recently, Staub helped schools in Massachusetts develop an anti-bystander curriculum, intended to encourage children to intervene against bullying. The program draws on earlier research that identified the causes of bystander behavior. For instance, older students are reluctant to discuss their fears about bullying, so each student tacitly accepts it, afraid to make waves, and no one identifies the problem—a form of pluralistic ignorance. Staub wants to change the culture of the classroom by giving these students opportunities to air their fears.

“If you can get people to express their concern, then already a whole different situation exists,” he said.

This echoes a point that John Darley makes: More people need to learn about the subtle pressures that can cause bystander behavior, such as diffusion of responsibility and pluralistic ignorance. That way they’ll be better prepared next time they encounter a crisis situation. “We want to explode one particular view that people have: ‘Were I in that situation, I would behave in an altruistic, wonderful way,’” he said. “What I say is, ‘No, you’re misreading what’s happening. I want to teach you about the pressures [that can cause bystander behavior]. Then when you feel those pressures, I want that to be a cue that you might be getting things wrong.’”

Research suggests that this kind of education is possible. One set of studies even found that people who attended social psychology lectures about the causes of bystander behavior were less susceptible to those influences.

But of course, not even this form of education is a guarantee against becoming a bystander. We’re always subject to the complicated interaction between our personal disposition and the demands of circumstance. And we may never know how we’ll act until we find ourselves in a crisis.

To illustrate this point, Samuel Oliner told the story of a Polish brickmaker who was interviewed for Oliner’s book, The Altruistic Personality . During World War II, a Jewish man who had escaped from a concentration camp came to the brickmaker and pleaded for help. The brickmaker turned him away, saying he didn’t want to put his own family at risk. “So is he evil?” asked Oliner. “I wouldn’t say he’s evil. He couldn’t act quickly enough, I suppose, to say, ‘Hide in my kiln,’ or ‘Hide in my barn.’ He didn’t think that way.”

“If I was the bricklayer and you came to me, and the Nazis were behind you and the Gestapo was chasing you—would I be willing to help? Would I be willing to risk my family? I don’t know. I don’t know if I would be.”

About the Authors

Jason Marsh

Jason Marsh is the executive director of the Greater Good Science Center and the editor in chief of Greater Good .

Dacher Keltner

Uc berkeley.

Dacher Keltner, Ph.D. , is the founding director of the Greater Good Science Center and a professor of psychology at the University of California, Berkeley. He is the author of The Power Paradox: How We Gain and Lose Influence and Born to Be Good , and a co-editor of The Compassionate Instinct .

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Bystander Effect

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Bystander Effect Definition

The bystander effect, also called bystander apathy, is a term in psychology that refers to the tendency of people to take no action in an emergency situation when there are others present. This phenomenon is highly studied in the field of sociology.

Bystander Effect Explained

Psychologically, there are many causes of the bystander effect. They range from thinking someone else is in charge, to not understanding the gravity of a situation because there are other people not taking action. In fact, Emergency First Responders must be trained to ignore this feeling and offer help whenever they see a situation they deem an emergency.

This concept was popularized after the 1964 killing of Kitty Genovese in New York City, giving rise to the term, “Genovese Syndrome”. The term bystander effect was coined in 1969 by John Darley and Bibb Latane to refer to the effect of certain social pressures on emergency responses in people.

As the above image shows, there are a number of potential reasons that people will use to ignore an emergency situation. The bystander effect is a subject of sociology because it is often an effect of “groupthink” or the “herd mentality”.

Bystander Effect Examples

In the event of an emergency, the first decision that a person needs to make is whether or not an emergency actually exists. This decision, when the individual is alone, is based on past experience and training. However, Latane and Darley concluded that in the presence of others, individuals will have a tendency to look to others for the correct decision. Seeing the inaction of others can develop a pluralistic response, causing a group to delay or fail to take action. Additionally, seeing the inaction of others can cause people to perceive the situation as less serious than it actually is.

The second decision that a person needs to make when an emergency situation is determined is what the appropriate course of action is. When there is a group of people also present, the responsibility of an individual person is less. In this situation, each individual in a large group may feel it is not their responsibility to act first. In order for a person to act first, they must assume a higher level of personal responsibility than their share.

The third decision component of emergency response is once the appropriate course of action is determined, the individual struggles with situational factors that inhibit them from acting. Latane and Darley showed in their experiments that individuals in the presence of strangers are far less likely to act than people in the presence of friends. Additionally, people who have even briefly met the victim are much more likely to respond.

Bystander Effect Experiments and History

On March 13, 1964, 28-year old Kitty Genovese was returning to her apartment in the Queens neighborhood of New York City when she was attacked by Winston Moseley. Moseley raped and stabbed Genovese to death outside her apartment while 38 people looked on and did nothing. The police were called, but dismissed the call as a “domestic dispute”. The national media picked up the story and public outrage towards the onlookers mounted.

In 1969, five years after the murder, social psychologists Bibb Latane and John Darley published “Bystander ‘Apathy’” in American Scientist . In this work, they conducted four separate experiments to test the effects of social interaction in emergency response. The experiments placed subjects in an artificial situation where a minor emergency event was taking place and correlated their response to the actions of actors within the experiment room.

The outcome of the experiments showed that there are social factors that influence the three different emergency management decisions.  The bystander effect has found a place in social psychology to explain the cumulative effects of several social tendencies during the occurrence of an emergency. The term “bystander apathy” is considered incorrect, since it was determined during the experiments that the subjects experienced genuine concern, although they did not act. However, this term remains widely used in news outlets for dramatic effect.

1. In what year was the term “bystander apathy” first used in an academic paper?

2. Which decision is not part of emergency response in an individual?

3. What factor is associated with increased emergency response in an individual?

4. Which part of Emergency First Responder training is meant to help responders overcome the bystander effect?

5. Which of the following describes the bystander effect?

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• Introduction

Bystander intervention

Social influence.

• Diffusion of responsibility
• Normative social influence

bystander effect

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• Table Of Contents

bystander effect , the inhibiting influence of the presence of others on a person’s willingness to help someone in need. Research has shown that, even in an emergency, a bystander is less likely to extend help when he or she is in the real or imagined presence of others than when he or she is alone. Moreover, the number of others is important, such that more bystanders leads to less assistance, although the impact of each additional bystander has a diminishing impact on helping.

Investigations of the bystander effect in the 1960s and ’70s sparked a wealth of research on helping behaviour, which has expanded beyond emergency situations to include everyday forms of helping. By illuminating the power of situations to affect individuals’ perceptions, decisions, and behaviour, study of the bystander effect continues to influence the course of social psychological theory and research.

The bystander effect became a subject of significant interest following the brutal murder of American woman Kitty Genovese in 1964. Genovese, returning home late from work, was viciously attacked and sexually assaulted by a man with a knife while walking home to her apartment complex from a nearby parking lot. As reported in the The New York Times two weeks later, for over half an hour 38 respectable, law-abiding people heard or saw the man attack her three separate times. The voices and lights from the bystanders in nearby apartments interrupted the killer and frightened him off twice, but each time he returned and stabbed her again. None of the 38 witnesses called the police during the attack, and only one bystander contacted authorities after Kitty Genovese died. (In 2016, following the death of the attacker, Winston Moseley, The New York Times published an article stating that the number of witnesses and what they saw or heard had been exaggerated, that there had been just two attacks, that two bystanders had called the police, and that another bystander tried to comfort the dying woman.)

The story of Genovese’s murder became a modern parable for the powerful psychological effects of the presence of others. It was an example of how people sometimes fail to react to the needs of others and, more broadly, how behavioral tendencies to act prosocially are greatly influenced by the situation. Moreover, the tragedy led to new research on prosocial behaviour, namely bystander intervention, in which people do and do not extend help. The seminal research on bystander intervention was conducted by American social psychologists Bibb Latané and John Darley, who found that bystanders do care about those in need of assistance but nevertheless often do not offer help. Whether bystanders extend help depends on a series of decisions.

Bystander decision-making

The circumstances surrounding an emergency in which an individual needs help tend to be unique, unusual, and multifaceted. Many people have never encountered such a situation and have little experience to guide them during the pressure-filled moments when they must decide whether or not to help. Several decision models of bystander intervention have been developed.

According to Latané and Darley, before helping another, a bystander progresses through a five-step decision-making process. A bystander must notice that something is amiss, define the situation as an emergency or a circumstance requiring assistance, decide whether he or she is personally responsible to act, choose how to help, and finally implement the chosen helping behaviour. Failing to notice, define, decide, choose, and implement leads a bystander not to engage in helping behaviour.

In another decision model, bystanders are presumed to weigh the costs and rewards of helping. Bystanders rationalize their decision on the basis of which choice (helping or not helping) will deliver the best possible outcome for themselves. In this model, bystanders are more likely to help when they view helping as a way to advance their personal growth, to feel good about themselves, or to avoid guilt that may result from not helping.

Social influence plays a significant role in determining how quickly individuals notice that something is wrong and define the situation as an emergency. Research has shown that the presence of others can cause diffusion of the responsibility to help. Hence, social influence and diffusion of responsibility are fundamental processes underlying the bystander effect during the early steps of the decision-making process.

If a bystander is physically in a position to notice a victim, factors such as the bystander’s emotional state, the nature of the emergency, and the presence of others can influence his or her ability to realize that something is wrong and that assistance is required. In general, positive moods, such as happiness and contentment, encourage bystanders to notice emergencies and provide assistance, whereas negative moods, such as depression , inhibit helping. However, some negative moods, such as sadness and guilt, have been found to promote helping. In addition, some events, such as someone falling down a flight of stairs, are very visible and hence attract bystanders’ attention. For example, studies have demonstrated that victims who yell or scream receive help almost without fail. In contrast, other events, such as a person suffering a heart attack , often are not highly visible and so attract little attention from bystanders. In the latter situations, the presence of others can have a substantial impact on bystanders’ tendency to notice the situation and define it as one that requires assistance.

In situations where the need for help is unclear, bystanders often look to others for clues as to how they should behave. Consistent with social comparison theory, the effect of others is more pronounced when the situation is more ambiguous . For example, when other people act calmly in the presence of a potential emergency because they are unsure of what the event means, bystanders may not interpret the situation as an emergency and thus act as if nothing is wrong. Their behaviour can cause yet other bystanders to conclude that no action is needed, a phenomenon known as pluralistic ignorance. But when others seem shocked or distressed, bystanders are more likely to realize an emergency has occurred and conclude that assistance is needed. Other social comparison variables, such as the similarity of other bystanders (e.g., whether they are members of a common in-group), can moderate the extent to which bystanders look to others as guides in helping situations. In sum, when the need for help is unclear, bystanders look to others for guidance. This is not the case when the need for assistance is obvious.

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Harvard expert says ‘bystander effect’ emboldens toxic culture of police violence

Since George Floyd died after police officer Derek Chauvin knelt on his neck for almost nine minutes on May 25, demonstrators across the country have gathered to protest police actions against African Americans. While most of the protests were calm, in several cities police officers  have used force against demonstrators and journalists under the justification of crowd control. The sight of officers in riot gear beating marchers, firing rubber bullets and chemical- or pepper-based irritants, and shoving activists has reignited questions about accepted practices in the nation’s law enforcement community.

Francesca Gino , Tandon Family Professor of Business Administration at Harvard Business School, studies leadership, the psychology of decision-making, and organizational behavior. She has written about how an organization can develop a culture that can turn harmful to its own people, to the success of its mission, and to its own reputation. In an interview, Gino discussed the circumstances surrounding Floyd’s killing, what they suggest about police culture in Minneapolis, and why it was unsurprising that the other officers on the scene didn’t stop Chauvin.

Francesca Gino

GAZETTE:   When a police officer acts inappropriately, a common defense is that it’s “one bad apple,” not an entire department. What are the signs that it’s “one bad apple” in an organization, and when it’s something more systemic?

GINO:   To me, the fact that no one reacted to the horrific situation, no one decided to help or stop Chauvin is a sign that the story is about more than one bad apple. It is difficult to make generalizations, but given how the other officers reacted, they clearly showed “bad apple” behavior as well.

GAZETTE:   Have you seen anything in the George Floyd incident to suggest there may be a toxic police culture at work?

GINO:   Culture is a pattern of beliefs and expectations that organization members share and that produce norms that powerfully shape how people behave. Cultural norms are expectations about appropriate behaviors; they are socially created standards that help us interpret and evaluate behavior. Through their behavior, the officers on site demonstrated that inexcusable behaviors are tolerated — whether just by them or the police more generally is difficult to say. And that makes for a toxic culture. It is every organization member’s responsibility, in their own leadership and work, to cultivate an effective culture.

“Why don’t people speak up more often when they see wrongdoing? One reason is the significant perceived risk of doing so,” said Harvard Business School Professor Francesca Gino. Jon Chase/Harvard file photo

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GAZETTE:   One of the chilling aspects of this incident is that three police officers stood by casually or assisted Chauvin while he pinned Floyd down until he died. What is at work psychologically when otherwise responsible people do bad things or allow bad things to happen? Why don’t people speak up more often when they see wrongdoing?

GINO:   One of the sad phenomena psychologists have studied for years now is the bystander effect. Basically, the research addresses the following question: Why is it that we look away even when atrocities are happening around us? One famous example that is often mentioned is the murder of a 28-year-old woman, Kitty Genovese, outside her apartment in the Queens neighborhood of Kew Gardens in the early morning of March 13, 1964. This case raised so many important questions: How could the neighbors look on and turn away as she was stabbed repeatedly on the street and in her apartment building? What did nobody act in a way that could be helpful? What did that collective inability to act reveal about us as human beings, our communities, and our belief systems?

This is not a story in isolation. Though the details of every story are different, and each of them is quite tragic in its own way, they also point to the bystander effect: We continue to look away in the face of danger.

The initial research was conducted by social psychologists John Darley and Bibb Latané. They wanted to show why the witnesses to Genovese’s murder, a case both followed avidly, behaved with such apathy, and whether they could quantify a minimum number of people present to create collective indecision. Their research found that the more people who witness a catastrophic event, the less likely any one person will do anything because each thinks someone else will take responsibility. Experiments that other researchers conducted in the years that followed suggest that in a crisis, pointing at a bystander and giving her directions to ask help or complete a task can override the robust bystander effect. Action over apathy is the greater struggle and more difficult choice, but it can prevail.

This research, I think, gets to [this] question. The three officers who stood by as officer Derek Chauvin held down George Floyd until he died may have been bystanders. But it is also possible, even in a situation as tragic and horrific as this one, that the inexcusable and immoral behavior of Chauvin became contagious. As I found in my own research, the unethical behavior of a bad apple can, in fact, become contagious. In one study, for instance, we found that when a confederate (a student with acting skills we hired for the study) cheated ostentatiously by finishing a task impossibly quickly and leaving the room with the maximum reward, participants’ level of unethical behavior increased when the confederate was an in-group member (a student just like them), but decreased when the confederate was an out-group member.

Why don’t people speak up more often when they see wrongdoing? There is a lot of research in management on why people do not speak up. One reason is the significant perceived risk of doing so. As I wrote recently, challenging the status quo threatens people’s status and relationships with supervisors and coworkers,  research shows . Speaking up in organizations can also result in  negative performance evaluation, undesirable job assignments, or even termination . Most people are aware of these potential costs; as a result, most stay quiet about bias, injustice, and mistreatment.

GAZETTE:   Who or what causes an organization’s culture to become toxic?

GINO:   When there’s a toxic culture in an organization, every leader who contributed to using behaviors that are not consistent with the values the organization stands for is to blame. As I always say to executives when teaching about culture, culture is inevitable. A culture will form in any organization. The question is whether it is one that helps or hinders the leaders’ ability to execute their strategy, stay scrappy, and be successful over the long run, however they define success.

GAZETTE:   What harm does a toxic culture do?

GINO:   Toxic cultures and workplaces, research finds, cause anxiety, stress, health problems, absenteeism, job burnout, counterproductive work behavior, and ultimately degrade productivity and increase turnover. For effective cultures to produce the effects they are intended to have, everyone has to uphold the culture even when it’s hard, it is not absolutely necessary, and no one is looking.

GAZETTE:   The Minneapolis police chief said he has been working to reform department culture, but has faced strong opposition from the police union. What can be done to root out a toxic culture once it has infiltrated an organization?

GINO:   Cultural transformation is possible . It starts with leaders first acknowledging the issues that are present that need to disappear and define how they negatively impact the workplace, and then identifying values to live by and behaviors that are consistent with those values. But it takes discipline. Culture works when it is consistent, coherent, and comprehensive. It is key for leaders to be consistent in communicating and reinforcing the values, and to have a clear vision in everything they do. Those who are aligned will stay while those who are misaligned will filter themselves out or should in fact be fired. Leaders are the ones who set the example and the tone of the organization’s culture through what they allow and what they model. Their actions must match their message. The values and behaviors identified need to be coherent with the strategic goals the organizations have and they need to be comprehensive.

This interview has been edited for clarity and length.

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