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Unpublished Paper
Federal Traffic Law: State Law, Reasonableness Norms, and the Fourth Amendment
ExpressO (2010)
  • Margaret Raymond
In Virginia v. Moore, 553 U.S. 164 (2008), the Supreme Court indicated that whether police comply with state law is irrelevant to whether they have acted reasonably under the Fourth Amendment. That’s an overstatement; there are times when the content of state law is critically relevant to whether police actions violate the constitution. One is the traffic stop. Federal courts assessing the constitutionality of traffic stops have developed a body of what might be deemed “federal traffic law” to determine the legality of such stops. The article analyzes and articulates the norms that the federal courts have developed to deal with a variety of recurring situations in which it is claimed that a stop was initiated because the driver violated state traffic law. As the article shows, the courts deem stops reasonable where drivers actually violated state traffic law, but also deem them reasonable in a range of situations where in fact drivers did not violate the law. These situations are typically the product of law enforcement mistakes. While the federal courts take a consistent approach to mistakes regarding facts or mistakes regarding which law applied to particular behavior, they are in conflict about situations in which the law enforcement officer conducting the stop was mistaken about whether the actor’s conduct was unlawful. The article concludes that these situations, where no law rendered the driver’s conduct unlawful, constitute one situation in which state law should conclusively determine the reasonableness of police conduct under the Fourth Amendment.
Publication Date
August 24, 2010
Citation Information
Margaret Raymond. "Federal Traffic Law: State Law, Reasonableness Norms, and the Fourth Amendment" ExpressO (2010)
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