The necessity doctrine aligns the private incentive and the social incentive for a property possessor to take a defensive action that prevents an invasion of his or her property from occurring. The model described here is also applicable to self-help in contracts.

The salvage of historic shipwrecks involves a debate between salvors, who wish to maximize profit, and archaeologists, who wish to preserve historical value. Traditionally, salvage of shipwrecks has been governed by admiralty law, but the Abandoned Shipwreck Act of 1987 transferred title of...

A key question in the literature on legal change is whether the law evolves via the conscious efforts of judges or is the result of invisible-hand processes. This paper confirms Priest's claim that when judges are unbiased, selective litigation alone can cause the law to evolve toward...

Standard models of law enforcement involve the apprehension and punishment of a single suspect, but in many contexts, punishment is imposed on an entire group known to contain the offender. The advantages of group punishment are that the offender is punished with certainty and detection costs...