The case: In 1963, three men were suspiciously walking back and forth in a block in Cleveland, Ohio, and a detective thought they were preparing to rob a store. He approached them, identified himself, then frisked them and found two concealed guns. One of the men was convicted for having the gun. The man appealed. The issue was whether police frisking violated the Fourth Amendment.
The decision: The Supreme Court held 8-1 that the search was reasonable since the men were acting suspiciously, warranting inquiry. If circumstances justify a belief that an individual is armed and dangerous, the justices ruled, the officer may pat down the outside of an individual's clothing.
Justice William O. Douglas, the lone dissenter, did not think the standard for search and seizures should have been lowered from "probable cause" to "reasonable suspicion." He wrote: "Yet if the individual is no longer to be sovereign, if the police can pick him up whenever they do not like the cut of his jib, if they can 'seize' and 'search' him in their discretion, we enter a new regime. The decision to enter it should be made only after a full debate by the people of this country."
This case opened up the police's ability to investigate activity they deem suspicious.