The Michigan Department of State Police (defendant) established a drunk driving checkpoint system. All vehicles passing through the checkpoint would be stopped and officers would briefly examine the drivers of the vehicles to determine if they were intoxicated. Where the officer believed the driver to be intoxicated, the driver would need to show his license and registration, further sobriety tests would be conducted, and arrest would be made if the tests so warranted. All other drivers would be immediately sent on their way and the average duration of each stop was twenty-five seconds. During seventy-five minutes of operation, 126 vehicles passed through one checkpoint, two drivers were detained for further sobriety testing and two drivers were arrested for drunk driving. Sitz (plaintiff) filed a complaint the day before the checkpoint went into effect, seeking declaratory and injunctive relief. The trial court held that the checkpoint violated the Fourth Amendment and the state appeals court affirmed.