Blame it on the Bystander: The Effects of Group Membership and Hindsight Bias on Bystander Culpability

Nearly one-third of sexual assaults take place with a bystander present, but research has shown that bystanders only intervene 36% of the time (Planty, 2002). Despite recent literature investigating bystander intervention in instances of sexual assault, very little research has been done on how others perceive bystanders when they fail to act. The current study examines hindsight bias (through outcome information) and group membership’s effects on perceptions of bystanders in a sexual assault situation. Participants read a vignette describing a potential sexual assault scenario where a bystander fails to intervene. Importantly, some participants received outcome information, which either explicitly confirmed an assault did or did not occur. Alternatively, some participants did not receive any outcome information. Participants indicated the extent to which they believed the bystander should have intervened as well as provided additional characteristic and situational judgments. While I saw no effect of group membership, outcome information impacted judgments made about the bystander. Participants believed that intervention was necessary when told a sexual assault occurred, but they blamed the bystander more when not given any outcome information.