The O. J. Simpson criminal trial was a social event that generated extensive public discourse and a search for causes. The dramatic differences of opinion between Black and White Americans about the case seemed to reflect broader disparities in social perception, particularly perceptions of the nature of racial/ethnic group relations in American society. This project involved the testing of a theoretical model, derived from social identity and intergroup attribution theory, to predict social perceptions associated with attitudes about the case. Black and White Americans were surveyed to assess their views of racial/ethnic group stratification, the importance of racial/ethnic group membership to self-identity, and perceptions of threat from the outgroup. These factors, in combination, were highly predictive of the intensity of respondents' beliefs about O. J. Simpson's guilt or innocence. This work will be of interest to social psychologists, sociologists, and others interested in how ordinary people interpret controversial social events, particularly those that have relevance to current social conflicts.