The use of sobriety checkpoints in Chicago has raised questions of racial bias, after an investigation by the Chicago Tribune found a disproportionate number of these checkpoints being conducted in minority areas of the city.

Sobriety checkpoints were first authorized by the U.S. Supreme Court case, Michigan v. Sitz. In this case, the majority opinion employed a balancing test, which weighed the states interests in preventing drunk driving against the Fourth Amendment's protection from unreasonable searches.

The court found that the 25-second delay that the average driver experienced at such stop was “slight” when balanced against the state's interest in reducing the “slaughter on our highways” attributed to drunk driving.

The Court of Appeals of Michigan had, in the underlying case, found the subjective intrusion unreasonable. The U.S. Supreme Court reversed stating the Michigan court had misread the Courts prior opinions. Ironically, after this case authorized sobriety checkpoints nationwide, the Michigan Supreme Court found them unreasonable under the state's constitution, so there are no sobriety checkpoints in that state.

The Illinois Supreme Court authorized temporary roadblocks for DUI purposes in 1985, but the current use of sobriety checkpoints in Chicago is troubling because of their concentration in minority areas.

The police claim they use roving DUI patrols in white areas, which are more effective at securing DUI arrests. However, sobriety checkpoints, because of their random nature, allow officers to stop all drivers without probable cause, which would be necessary for roving patrols.

This creates the appearance by the Chicago police of using DUI checkpoints as “pretext” to gain broader surveillance of minority drivers than would be permitted by the Fourth Amendment. Minority communities are sensitive to pretext issues simply because the outcomes of many of these traffic stops have proven deadly.

Source: chicagotribune.com, “Chicago police DUI checkpoints still concentrated in minority neighborhoods” Angela Caputo, September 11, 2015