DUI checkpoints are constitutionally allowed despite their intrusion on individual liberties, according to a FindLaw article. The Supreme Court decided the issue in 1990 in the case of Michigan Dept. of State Police v. Sitz. The Supreme Court has left the decision to use DUI checkpoints to the states.
In deciding the question whether a checkpoint amounted to an unreasonable intrusion, the Supreme Court determined that using checkpoints was a minimal invasion and an acceptable measure to protect society from the dangers of drunk driving, notes FindLaw. The court specifically found that the duration of the waiting time at checkpoints was very minimal and the search not overly burdensome to the average driver.