Police observed D's unoccupied vehicle illegally parked in the restricted zone. At approximately 3 a. m., the officer issued an overtime parking ticket and placed it on the car's windshield. At approximately 10 o'clock on the same morning, another officer issued a second ticket for an overtime parking violation. The car was towed to the city impound lot. A police officer observed a watch on the dashboard and other items of personal property located on the back seat and back floorboard. The car door was then unlocked and, using a standard inventory form pursuant to standard police procedures, the officer inventoried the contents of the car, including the contents of the glove compartment, which was unlocked. He found marihuana contained in a plastic bag. D was arrested on charges of possession of marihuana. The motion to suppress the evidence was denied. D was convicted after a jury trial and sentenced to a fine of $100 and 14 days' incarceration in the county jail. The Supreme Court of South Dakota reversed the conviction. It concluded that the evidence had been obtained in violation of the Fourth Amendment prohibition against unreasonable searches and seizures. The Supreme Court granted certiorari.