City of Indianapolis v. Edmond

Summary

Justice O'Connor, joined by Stevens, Kennedy, Souter, Ginsburg, and Breyer, held that Indianapolis's suspicionless vehicle checkpoints violated the Fourth Amendment because their primary purpose was ordinary crime control through narcotics detection. Legitimate secondary purposes did not cure that defect, and the relevant purpose inquiry concerns the program rather than individual officers' motivations. An exterior dog sniff did not itself transform the seizure into a search. Chief Justice Rehnquist dissented, joined by Thomas and, as to Part I, Scalia, arguing that the checkpoints were objectively reasonable because they also served legitimate licensing and sobriety purposes with minimal intrusion. Thomas separately questioned the correctness of the Court's earlier checkpoint decisions but would follow them and uphold this program because respondents had not requested their overruling.