In recent years it has become quite usual to view legal decisions in terms of consideration of the values affected by deciding the case for or against a particular party. Often deciding for, say, the plaintiff will promote one value at the expense of another. Precedents are then supposed to guide the way in which this conflict is resolved. In this paper we will consider a series of cases exploring the so-called automobile exception to the requirement of the Fourth Amendment protecting against unreasonable search of persons, houses, papers, and effects. These cases highlight a conflict between the value of law enforcement and the value of privacy as protected by the Fourth Amendment, and will be used to illuminate questions about the treatment of value conflicts arising from previous work in AI and Law.