DUI roadblocks or sobriety checkpoints are a common tool used to detect the drunk driver. Law enforcement agencies modeled this approach on the success of roadside safety checks and license/registration inspections. In this process the police agency will set up a roadblock on a highway and if the selected driver's speech sounds slurred or his breath smells of alcohol, he will be asked to leave the car and perform a field sobriety tests at the scene.
In 1990, the United States Supreme Court reversed a state supreme court decision that declared DUI sobriety checkpoints unconstitutional. In Michigan Department of State Police v. Sitz, 496 U.S. 444 (1990), the Court held that the checkpoint operation in question did not violate the Fourth Amendment's prohibition against unreasonable searches and seizures.
The Court's 6-3 decision authored by Chief Justice Rehnquest was not an unexpected result. The ruling recognized that roadblocks do constitute a "seizure" within the bounds of the Fourth Amendment, but the Chief Justice reasoned that the intrusion on individual liberties must be weighed against the need and effectiveness of the roadblock. In the end, the interests in reducing alcohol-related fatalities outweighed the intrusion on human privacy rights and sobriety checkpoints were deemed constitutionally acceptable.
Confronted with a DUI case involving a roadblock/checkpoint, DUI lawyers must consider the adequacy of the procedures employed: Was the roadblock conducted in a constitutionally permissible manner? Even Chief Justice Rehnquist implicitly acknowledged that there must exist "guidelines" concerning such matters as location, publicity, and roadblock operation. Note that in Sitz the roadblock was set up only after a "Sobriety Checkpoint Advisory Committee" had been appointed to establish guidelines; this committee consisted of representatives of the state police, local police, prosecutors, and the University of Michigan Transportation Research Institute.
But what are the "guidelines"? Rehnquist's opinion in Sitz leaves the question of minimal adequacy of such standards unanswered, presumably to be determined on a case-by-case basis. Counsel may find some guidance in the decisions of sister states. In one of the most influential of these pre-Sitz cases, the California Supreme Court set forth what it felt to be the procedural safe-guards required for a DUI roadblock to comply with the Constitution. Ingersoll v. Palmer, 743 P.2d 1299 (Cal. 1987).
For further information about sobriety checkpoints or drunk driving roadblocks, see: