While most DUI/DWI stops are made by individual police officers on the road, there may be times when you encounter a sobriety checkpoint. There are a number of rules—created by the State Supreme Court—that govern how sobriety checkpoints are set up and conducted, rules that you should be familiar with. One of the most important is that the location of the checkpoints must be announced to the public before they are set up, commonly in newspapers and on the internet. There is nothing wrong with learning where the checkpoints will be in order to avoid them. That is your legal right.
Another important thing to know is that not all cars are stopped. Vehicles are selected by a mathematical formula, not by how people look or drive. Finally, checkpoints must minimize the average time each motorist is detained. This means that the officer cannot ask you to step out of your car or ask to you to take any tests unless there are noticeable signs of impairment—erratic driving, the smell of alcohol on the breath, slurred speech, glassy eyes, etc. If you do not show any of these signs, you must be allowed to drive on. If the officer does decide that you display signs of impairment, you will be directed to a separate area for field sobriety tests. From this point forward, it is no different from being pulled over by a police officer.