There is an inherent tension between the idea that individuals have certain inalienable (natural) rights and the economist's postulate that the rate if utilization of anything whose production requires scarce resources must be limited by considerations of opportunity cost. Remarks about rights to life, liberty, health, justice and the like are readily inserted into political pronouncements, legislative preambles and court decisions, but they (should) cause economists to raise questions about costs and quantities. Unfortunately, neither in ordinary language nor in the jargon of moral philosophy can such ultimate desiderata as liberty and justice be related to costs or quantities. Hence in the first section we sketch a model of social choice in which the necessary relationships can be defined. In section II, we give instances where, despite protestations to the contrary, the Law Enforcement System (LES) has made de facto reductions of citizen rights (liberties) in order to increase the efficiency if law enforcement. The final section considers some of the normative implications suggested by the positive arguments of section II.