Today the Supreme Court handed down what is probably the most interesting Fourth Amendment case of the Term, Herring v. United States, the case on whether the Fourth Amendment required suppression when a negligent error in a police database led an officer to incorrectly believe that there was an arrest warrant out for a suspect and therefor to arrest him. Readers may recall that after reading the briefs and the argument transcript, I had concluded that Herring was a narrow but clear win for the government. Somewhat to my surprise, the case became a 5-4 decision, with Chief Justice Roberts writing the majority opinion with the four liberal Justices in dissent, in what is almost a replay of similar issues 14 years ago in Arizona v. Evans, 514 U.S. 1 (1995).
Roberts’ opinion adopts the now-standard balancing approach to the exclusionary rule, in which the court balances the costs of exclusion of the evidence to the public safety to the deterrent benefit to the police, and concludes that under this balance the exclusionary rule does not apply. Here’s Robert’s basic argument, with citations and internal quotations omitted, as numbered in the opinion:
1. The fact that a Fourth Amendment violation occurred