Through its antitrust enforcement system, society allocates resources to deter anticompetitive behavior. Antitrust enforcement is costly because prosecutors and judges mischaracterize some competitive or efficiency-enhancing behavior as horizontal collusion. In this early application of the Polinsky-Shavell argument about the tradeoff between the probability and magnitude of fines, this essay argues that, given prosecutorial and judicial error, society will not optimally allocate its antitrust enforcement resources by threatening price fixers with exorbitant economic penalties that have only a minimal probability of being enforced.