United States v. Robinson, 414 U.S. 218 (1973), was a case in which the United States Supreme Court held that "in the case of a lawful custodial arrest a full search of the person is not only an exception to the warrant requirement of the 4th Amendment

Fourth Amendment to the United States Constitution

The Fourth Amendment to the United States Constitution is the part of the Bill of Rights which guards against unreasonable searches and seizures, along with requiring any warrant to be judicially sanctioned and supported by probable cause...

, but is also a reasonable search under that Amendment."

Facts

A D.C. Metro officer stopped a 1965 Cadillac based on reliable information that the driver's operating license had been revoked. All three occupants exited the car, and the officer arrested the driver, Robinson. (For purposes of the Court's opinion, it was assumed that Robinson's full-custody arrest was valid.) The officer proceeded to search Robinson, and felt a package whose contents the officer could not immediately identify. Upon removing the package—a crumpled cigarette packet—and opening it, the officer discovered "14 gelatin capsules of white powder" that turned out to be heroin.

Holding

No it did not. According to the Robinson Court "in the case of a lawful custodial arrest a full search of the person is not only an exception to the warrant requirement of the 4th Amendment, but is also a reasonable search under that Amendment."