What is the test for a police search warrant for a car stop?

We reaffirmed these principles recently in People v. May 81 N.Y.2d 725, 593 N.Y.S.2d 760, 609 N.E.2d 113, supra, where the defendant and a female companion were sitting in a parked car on a deserted street known for criminal activity. When two police officers in a patrol car approached with red turret lights and a spotlight, defendant started his car and slowly pulled away. Defendant was ordered to pull over. We held that the police officers' premise for that order--the common-law right of inquiry--did not satisfy Fourth Amendment standards: "the stop was proper only if the officers had a reasonable suspicion of criminal activity" (id., at 727, 593 N.Y.S.2d 760, 609 N.E.2d 113).