There is a common perception that arbitrariness in the law is a bad thing. It is not. This essay seeks to explain why, and to clarify when arbitrariness is a problem.
It is nearly impossible to devise laws that are not in some respect arbitrary. Sometimes the general thrust of the law is not arbitrary but the details are. Start with an uncontroversial law: the prohibition on burglary. Everybody agrees that burglary should be illegal and everybody agrees on why burglary should be illegal. Not everybody agrees, however, on exactly what the law should say. English common law defined burglary as breaking and entering into the dwelling house of another, during the nighttime, for the purpose of committing theft or another crime. It was a capital offense. The definition has changed over time. Today, nearly all jurisdictions have done away with the requirement that it happen at night. Most jurisdictions have also created lesser, related offenses for breaking into other structures and even aut