The purpose of DUI checkpoints, it seems, is to catch drunk drivers. Armed with a sure-fire method of detecting impairment – a breathalyzer – it would seem that a sobriety checkpoint would be an effective way to snag someone who is driving under the influence. Just set up shop somewhere unexpected, and bang! You’re busted.
But it doesn’t work that way. You’ve probably noticed news items that mention where the next DUI checkpoint will be.
Some people consider that a head-slap-worthy mistake. Announce the checkpoint early? So that drunks can avoid it? How dumb can you be?
But it’s not dumb, or a mistake: it’s the law. In states that employ DUI checkpoints to catch drunk drivers, the time and place must be announced beforehand.
The law stems from a Supreme Court ruling some years ago. Checkpoints were controversial then, as they are now. Supporters note that they are valuable as a way to catch impaired drivers and deter others from drinking and driving. Opponents consider them a violation of the Fourth Amendment: searching a person without a warrant is against the constitution.
The Necessity of Prior Notice
The Supreme Court ruled that DUI checkpoints are indeed constitutional, but only if certain procedures are followed:
- Law enforcement must announce to the public the date and time of the checkpoint
- There must be a valid reason for the checkpoint, e.g. drunk driving arrests or collisions are more frequent on a given route
- There must be a specific plan designating which vehicles are to be stopped, e.g. every tenth vehicle
These guidelines are in place to prevent police-state tactics such as singling out drivers because of their race, appearance, or political views (as on a bumper sticker). They also prevent unconscious biases from influencing the process.
Why DUI Checkpoints Work Anyway
Even with prior announcement, sobriety checkpoints do indeed catch a lot of drunk drivers, as well as violators of other types. Just as important, they act as a very powerful deterrent. Other motorists who are on the way to a restaurant or bar will pass the checkpoint and decide it’s a bad idea to drink and drive.
These guidelines have not made DUI checkpoints universally accepted. Twelve states do not allow checkpoints, either because the conflict with state laws or because the states interpret the U.S. Constitution in a way that prohibits them.
If you see a notice about a sobriety checkpoint, don’t shake your head at the senselessness of it all. The publicity is a protection of your rights, and in any case, the checkpoint will do its job and keep drunk drivers off the road, either through arrest or deterrence.