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BranchOut! Human Minds: A Crowd Full of Bystanders- The Bystander Effect and Pluralistic Ignorance

On the night of March 13th, 1964 in Queens, New York, Catherine Susan “Kitty” Genovese was murdered by Winston Moseley. Many residents around the area heard the hour-long attack, but no one came to help or even called the police. This case sounds more like a scene from a movie rather than an actual event. How can someone, let alone a whole neighborhood, ignore the cries of a murder victim? Unsurprisingly, this case caught the attention of city dwellers, crime investigators, and psychologists. Why did such a horrible yet preventable event occur? To find an explanation, Latané and Darley, two social psychologists, led an investigation and called this phenomenon the “bystander effect.” As time passed, more and more research was conducted to explain this behavior. While researchers are still looking for a concrete answer, one possible explanation is “pluralistic ignorance.”

Simply put, the bystander effect is the tendency of an individual to not intervene in a situation if more people are around. In many psychology textbooks, the bystander effect is interpreted as a three-step process (Rendsvig, 2014). First, one must become aware of the event. If one does not even know the event is happening, there is no way he/she would help. Secondly, if noticed, the individual must be able to process the event internally. Especially if the situation is ambiguous, it may be hard to tell if something is truly wrong. Lastly, when the individual interprets the situation as an emergency or problem, they will have to decide what to do. This is an easy decision if alone, but in a crowd, people might be uncertain whether or not they are qualified to handle the situation. This is called “diffusion of responsibility”, and the likelihood of anyone in a crowd intervening diminishes dramatically (Rendsvig, 2014).

But how do individuals decide if they should intervene? This is where pluralistic ignorance comes into the picture. Pluralistic ignorance often refers to a situation where everyone in a group believes that other members agree with a “given proportion/endorses a given norm,” while in reality, no one “believes/endorses it” at all (Bjerring, Hanson, Lee, & Pedersen, 2014, Rendsvig, 2014). While it seems harmless at first glance, it can lead to poor group and individual decisions. Scientists have a wide stance on why this phenomenon occurs. Some say it is caused by “doubt” in oneself (Rendsvig, 2014), while others contribute it to “fear of embarrassment” (Miller and McFarland, 1987).

Though researchers are unclear why pluralistic ignorance occurs, they certainly know the implementations of it. A classroom is a good example mentioned by Millar and McFarland (1987). For instance, a teacher just finishes going over some new material and asks the students if they have any questions. While none of the students fully understand the new concept, none of them raise their hands. Because students don’t see any of their classmates raise their hand, they believe that no one believes the material is hard. Since they do not want to publicly admit they are the only ones who don’t understand, their question remains unanswered. This is an example where pluralistic ignorance can lead to poor individual decisions.

Another example is in a business setting mentioned by Rendsvig (2014). A company is performing poorly, and a meeting is held amongst the board of directors to discuss future plans. While everyone believes something needs to change in the company’s strategy, they cast doubt on their beliefs. Therefore, all the board members look at their fellow co-workers for answers, trying to gather more information to see if their view is similar to others. Since everyone is waiting for others to say something first, no one suggests their ideas for a new strategy. Additionally, every individual assumes that no one wants to change the company’s strategy, and doesn’t intervene with their ideas. In this case, pluralistic ignorance leads to a poor group decision.

There are still many unanswered questions regarding the bystander effect and pluralistic ignorance. Is there a way to prevent this from happening? Does social media have an effect on these two phenomena? Researchers are still digging into these questions. Of course, one cannot completely prevent the bystander effect from occurring, nor can one change his/her natural human psychological instincts. However, it’s important to learn the importance of speaking up when something does not look right. While not every one of us will encounter something like the Genovese case first hand, everyone will definitely witness and experience the effects of being a bystander.



Bjerring, J.C., Hansen, J.U. & Pedersen, N.J.L.L. On the rationality of

pluralistic ignorance. Synthese 191, 2445–2470 (2014).

Miller, D. T., & McFarland, C. (1987). Pluralistic ignorance: When similarity is interpreted as dissimilarity. Journal of Personality and Social Psychology, 53(2), 298–305.

Rendsvig, R. (2014). Pluralistic ignorance in the bystander effect: informational dynamics of

unresponsive witnesses in situations calling for intervention. Dordrecht, 191(11), 2471-2498.

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