Group Processes &Intergroup Relations, Ahead of Print.
While most people believe they would speak up against prejudice, many fail to do so. We identify a harmful consequence of such inaction through examining its impact on bystanders’ own prejudice. Across four studies in two countries (N = 1,003) using a behavioral paradigm and experimental pretest–posttest design, participants witnessed prejudice and discrimination against an outgroup minority (Jewish/Roma in Hungary, Muslim/Latinx in US). Drawing on self-justification theories, we predicted and found across Studies 1–3 that those who had an opportunity but did not confront, endorsed more negative intergroup attitudes following the incident both compared to their own prior attitudes and to control groups—that is, those who witnessed the same prejudice but had no opportunity to confront and those who did not to confront different (nonintergroup) prejudice. In Study 4, the proposed effect occurred only among those who initially valued confronting. We suggest that failure to speak up amplifies prejudice in society.