Gary S. Becker's economic approach to crime and punishment was essentially static. In the sequel Davis, Friedman et al., Gerchak et al., Leung, and others addressed the question of optimal law enforcement by including intertemporal aspects. The present paper considers a rational offender who optimizes his/her criminal career by taking into consideration that the severity of the punishment for a given crime depends on the offender's prior criminal record. A life cycle model for describing the behaviour of a recidivous criminal is formulated in terms of optimal control theory, the criminal's record being the state variable. In particular, we study the impact of an offender's prior criminal record on the punishment of a given crime. It should be stressed that such an analysis may yield important insight into the design of optimal law enforcement policies. A numerical phase-diagram analysis and, moreover, a sensitivity analysis are provided in order to show which strategies are expedient in reducing the amount of criminal activities and which make it even worse.
