Bystander Apathy

Bystander apathy describes the tendency of individuals to be less likely to offer help to a victim when other people are present than when they are alone. The effect was documented experimentally in the 1960s, prompted in part by a widely reported case in which onlookers failed to intervene during an attack, leading psychologists to study why the presence of others so often suppresses helping behavior. Researchers attribute it chiefly to diffusion of responsibility, in which each bystander assumes someone else will act, and to social influence, in which people read others' inaction as a cue that intervention is unnecessary.