Data from a random sample of mail survey respondents were used to test the "invariance thesis" (N = 1,681). Multiplicative interaction effects between the key antecedents of legitimacy (measured separately for obligation to obey and trust in the police) and various demographic categories, prior experiences, and perceived neighborhood conditions were estimated in a series of multivariate regression equations. The effect of procedural justice on police legitimacy was largely invariant; however, regression and marginal results show that procedural justice has a larger effect on trust in law enforcement among people with prior victimization experience compared to their counterparts. In addition, the distributive justice effect on trust in the police was more pronounced for people who had greater fear of crime and perceived higher levels of disorder in their neighborhood. These results suggest that Tyler's process-based model is a "general" theory of individual police legitimacy evaluations. The police can improve their legitimacy by ensuring procedural fairness during citizen interactions. The role of procedural justice also appears to be particularly important when the police interact with crime victims. (Publisher abstract modified)