United States v. Chadwick
United States v. Chadwick, 433 U.S. 1 (1977), was a decision by the United States Supreme Court, which held that, absent exigency, the warrantless search of double-locked luggage just placed in the trunk of a parked vehicle is a violation of the Fourth Amendment and not justified under the automobile exception.
Source: Wikipedia — United States v. Chadwick (CC BY-SA 4.0)