I noticed in the newspaper that the police department is running DWI checkpoints to catch drunk drivers here in Jefferson City at the end of February.
The deal is that the police get to stop your car and check you out to see if you are under the influence. Most of the time, stopping and examining citizens without ANY cause whatever is considered a blatant violation of the fourth amendment protection against search and seizure.
But that protection was permanently swept away by a U.S Supreme Court decision in 1990. The United States Supreme Court held that a state’s use of a highway sobriety checkpoint does not per se violate the Fourth Amendment to the United States Constitution. There are maybe half a dozen states that still consider such stops as unconsitutional, but Missouri is not one of them.
The police cannot, however, simply stop whomever they want, whenever they want. If they want to use a DWI roadblock, the police are required to create a detailed plan in advance.
They must have their plan in writing and have a supervising officer present throughout the time of the roadblock. They have to design it to catch the most offenders while creating minimum delays for everyone else and to do it in a safe manner.
The police sometimes get clever in setting up such roadblocks. A sign on the highway will say “Sobriety checkpoint ahead – be prepared to stop.” The police then setup the roadblock–not on the highway–but at the next exit.
The idea is that drunk drivers will “select” themselves by taking the exit to avoid the roadblock. Like checking into a roach motel. Too late, the driver realizes, he put his head in the noose.
Of course, once the police have a car stopped and the window is rolled down, the party is over in the time it takes to smell the driver’s breath.
Any driver arrested for a DWI or other charge needs to talk to an attorney as soon as possible. This goes double when the arrest stems from a roadblock situation. DWI prosecutions are always tricky. The legal & scientific requirements are complex. They are made even more complicated by checkpoint requirements.
Cops are human and they make their share of screw-ups. No defendant should plead guilty to a crime without knowing if the state actually has a legal case against them.