Bystander Effect In Psychology

By Udochi Emeghara

Reviewed bySaul McLeod, PhD&Olivia Guy-Evans, MSc

On This Page:

1. Definitions
2. Kitty Genovese
3. Decision Model of Helping
4. Why It Occurs
5. Bystander Experiments
6. Critical Evaluation

Take-home Messages

• The bystander effect is a social psychological phenomenon where individuals are less likely to help a victim when others are present. The greater the number of bystanders, the less likely any one of them is to help.

• Factors include diffusion of responsibility and the need to behave in correct and socially acceptable ways.
• The most frequently cited real-life example of the bystander effect regards a young woman called Kitty Genovese, who was murdered in Queens, New York, in 1964 while several of her neighbors looked on. No one intervened until it was too late.
• Latané and Darley (1970) proposed a five-step decision model of helping, during each of which bystanders can decide to do nothing:
1. Notice the event (or in a hurry and not notice).
2. Interpret the situation as an emergency (or assume that as others are not acting, it is not an emergency).
3. Assume responsibility (or assume that others will do this).
4. Know what to do (or not have the skills necessary to help).
5. Decide to help (or worry about danger, legislation, embarrassment, etc.).

• Latané and Darley (1970) identified three different psychological processes that might prevent a bystander from helping a person in distress: (i) diffusion of responsibility; (ii) evaluation apprehension (fear of being publically judged); and (iii) pluralistic ignorance (the tendency to rely on the overt reactions of others when defining an ambiguous situation).
• Diffusion of responsibility refers to the tendency to subjectively divide personal responsibility to help by the number of bystanders present. Bystanders are less likely to intervene in emergency situations as the size of the group increases, and they feel less personal responsibility.

The bystander effect can cause someone to hesitate and refrain from taking action or offering help in a situation, assuming that others will step in or feeling less responsible when they see others present.

What is the bystander effect?

The term bystander effect refers to the tendency for people to be inactive in high-danger situations due to the presence of other bystanders (Darley & Latané, 1968; Latané & Darley, 1968, 1970; Latané & Nida, 1981).

Thus, people tend to help more when alone than in a group.

The implications of this theory have been widely studied by a variety of researchers, but initial interest in this phenomenon arose after the brutal murder of Catherine “Kitty” Genovese in 1964.

Through a series of experiments beginning in the 1960s and 1970s, the bystander effect phenomenon has become more widely understood.

Kitty Genovese

On the morning of March 13, 1964, Kitty Genovese returned to her apartment complex, at 3 am, after finishing her shift at a local bar.

After parking her car in a lot adjacent to her apartment building, she began walking a short distance to the entrance, which was located at the back of the building.

As she walked, she noticed a figure at the far end of the lot. She shifted directions and headed towards a different street, but the man followed and seized her.

As she yelled, neighbors from the apartment building went to the window and watched as he stabbed her. A man from the apartment building yelled down, “Let that girl alone!” (New York Times, 1964).

Following this, the assailant appeared to have left, but once the lights from the apartments turned off, the perpetrator returned and stabbed Kitty Genovese again. Once again, the lights came on, and the windows opened, driving the assaulter away from the scene.

Unfortunately, the assailant returned and stabbed Catherine Genovese for the final time. The first call to the police came in at 3:50 am, and the police arrived in two minutes.