WASHINGTON – The Supreme Court has ruled that police need a warrant to search the vehicle of someone they have arrested if the person is locked up in a patrol cruiser and poses no safety threat to officers.

The court’s 5-4 decision Tuesday effectively limits the authority of police to search a vehicle immediately after the arrest of a suspect.

Justice John Paul Stevens said in the majority opinion that if a car’s passenger compartment is not within reach of a suspect who has been removed from the vehicle, then police have little reason to rush to a warrantless search.

The decision backs an Arizona high court ruling in favor of Rodney Joseph Gant, who was handcuffed, seated in the back of a patrol car and under police supervision when Tucson, Ariz., police officers searched his car. They found cocaine and drug paraphernalia.