The Effects of the Standard for Search Warrants

Abstract

We analyze the effects of the evidence standard for search warrants in an economic model of crime and search. If the warrant standard is initially below a certain positive threshold, increasing it actually reduces crime as well as searches. Moreover, the positive threshold is higher if searches are more preventive. If the warrant standard is initially high enough, increasing it tends to increase crime and reduce wrongful searches. However, if the police do not care too much about whether or not they search the innocent, increasing the standard also increases effort by the police to gather initial evidence non-invasively before seeking to perform invasive searches. Thus, increasing the standard might not greatly increase crime because greater police effort tends to reduce crime; but it might significantly reduce wrongful searches because greater police effort directly increases the accuracy of the police's initial evidence. The results provide efficiency arguments for a right against unreasonable searches.