by John Marshall Harlan, Coolidge v. New Hampshire — Concurrence
“ Only rarely can it be said that evidence seized incident to an arrest is truly unexpected or inadvertent. Indeed, if the police officer had no expectation of discovering weapons, contraband, or other evidence, he would make no search. It appears to me that the rule adopted by the Court today, for all practical purposes, abolishes seizure incident to arrest. The majority rejects the test of reasonableness provided in the Fourth Amendment and substitutes a per se rule-if the police could have obtained a warrant and did not, the seizure, no matter how reasonable, is void. ”
