bystander effect

n. The bystander effect is a well-established social psychological phenomenon whereby an individual is slower and less likely to respond to a person in distress if others are present. Research into this phenomenon was a result of a highly publicized case in which a woman (Catherine "Kitty" Genovese) was brutally attacked while 38 of her neighbors watched. Kitty's death triggered hundreds of investigations into how so many people could stand by and do nothing to help the victim. The bystander effect has been found in laboratory settings and in real-life emergency and nonemergency situations.

Researchers suggest that social influence, evaluation apprehension, and diffusion of responsibility can help explain the bystander effect. Additionally, individuals are less likely to engage in the bystander effect when they feel good, feel guilty, know how to provide assistance, perceive the victim as needing and deserving help, observe others helping, and/ or know the victim.                                                       

- lmb