Moral and conventional violations are usually judged differently: Only moral violations are treated as independent of social rules. To investigate the cognitive processing involved in the development of this distinction, undergraduates (N = 34), adolescents (N = 34), and children (N = 14) read scenarios presented on a computer that had 1 of 3 endings: moral violations, conventional violations, or neutral acts. Participants judged whether the act was acceptable or unacceptable in a condition in which social rules were assumed, or in a condition in which they imagined the absence of rules (rule-removed condition). At all ages reaction times (RTs) were faster for moral than conventional violations when a rule was assumed. RTs in the rule-removed condition were longer than in the rule-assumed condition, only for adults' moral judgments. In addition to this age difference, adolescents made more normative judgments than children. These findings extend previous work by showing different time courses of processing conventional versus moral violations and revealing age-related differences in the tendency to make normative judgments. (Contains 1 table and 2 figures.)