Bystander Effect: Someone Will Help, Right?


Imagine walking back home from a party late one night when you hear a woman screaming for help. You look across the street and notice a man kicking and screaming at the woman lying on the ground. Near the victim are four people watching the attack take place. You decide that one of the bystanders has probably already called the police and you don’t need to do anything further to help the victim. However, no one had yet done anything to help the victim. 


The reason why there were multiple bystanders but none of them intervened can be attributed to the bystander effect. This effect makes it less likely for people to intervene in emergencies if there are others around them. The more people there are, the more each bystander is discouraged from doing something about the problem. This effect is often the result of the bystander feeling uncertain about their role in the situation. He/she might believe someone else is responsible for seeking help or someone else already did something to help. The bystander might also feel like they are a part of the group and need to do whatever the other bystanders do.

Definition of Bystander Effect

The bystander effect takes place when the presence of others discourages an individual from intervening in an emergency.


After the murder of  Kitty Genovese in 1964, social psychologists, John M. Darley and Bibb Latané first became interested in the bystander effect. Kitty’s death received much attention because she was violently stabbed while numerous individual’s stood by, but failed to intervene. 

Darley and Latane first tested and popularized the bystander effect in 1968. The experiment they used to test it has become one of the experiments with the most reliable  results in social psychology. In this experiment, the participant is either alone or among a group of people when an emergency takes place. Psychologists measure how long it takes the participants to intervene- if they do. Latane and Rodin found that 70 percent of the participants called or helped the victim when they were alone. On the other hand, only 40 percent helped when there were others in the room with them-- this is a highly considerable margin!

Why Care?

The bystander effect is an extremely important topic since the wellbeing of others might depend on you. You can utilize this newfound knowledge to help others when they are in need, regardless of what other people around you are doing. It is too often that we look around the room before we act, even if we know and understand that we need to intervene. This knowledge can be your weapon against the belief that others are obligated to do something, when, in fact, you can do something at that moment!

Think Further

  1. Can you think of an instance in which you knew someone needed help, but didn’t intervene? 
  2. If so, what thoughts prevented you from acting on behalf of the victim?
  3. Do you think that if the victim is someone you know, the bystander effect might not take place?


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Learn More

  1. Darley, J. M. & Latané, B. (1968). “Bystander intervention in emergencies: Diffusion of responsibility”. Journal of Personality and Social Psychology. 8: 377–383. doi:10.1037/h0025589
  2. Fischer, Peter; Krueger, Joachim I.; Greitemeyer, Tobias; Vogrincic, Claudia; Kastenmüller, Andreas; Frey, Dieter; Heene, Moritz; Wicher, Magdalena; Kainbacher, Martina. “The bystander-effect: A meta-analytic review on bystander intervention in dangerous and non-dangerous emergencies”. Psychological Bulletin. 137 (4): 517–537. doi:10.1037/a0023304.
  3. Darley, J. M., & Latane, B. (1970). The unresponsive bystander: why doesn’t he help? New York, NY: Appleton Century Crofts.