Why is it that some people respond in a more negative way to procedural injustice than do others, and why is it that some people go on to defy authority while others in the same situation do not? Personality theorists suggest that the psychological effect of a situation depends on how a person interprets the situation and that such differences in interpretation can vary as a function of individual difference factors. For example, affect intensity-one's predisposition to react more or less emotionally to an event-is one such individual difference factor that has been shown to influence people's reactions to events. Cross-sectional survey data collected from (a) 652 tax offenders who have been through a serious law enforcement experience (Study 1), and (b) 672 citizens with recent personal contact with a police officer (Study 2), showed that individual differences in 'affect intensity' moderate the effect of procedural justice on both affective reactions and compliance behavior. Specifically, perceptions of procedural justice had a greater effect in reducing anger and reports of non-compliance among those lower in affect intensity than those higher in affect intensity. Both methodological and theoretical explanations are offered to explain the results, including the suggestion that emotions of shame may play a role in the observed interaction.