Police departments often resort to adding more patrols on holidays and on other occasions. In Connecticut and other states, sometimes the stepped-up enforcement takes the form of DUI checkpoints, in which police give notice that they are setting up shop at certain locations.
There is a very good reason why they give this notice: it's the law. In 1990, the U.S. Supreme Court ruled that checkpoints are constitutional, but only so long as law enforcement follows appropriate guidelines. One of those guidelines is providing notice of the checkpoints in advance.
Giving this notice does not mean, however, that police can just pull over anyone they want. Officers still need a legitimate reason for pulling someone over. After all, the Fourth Amendment protection against unreasonable search and seizure requires no less.
It's also important to remember that sometimes state constitutions provide even greater protections than the federal constitution. Consider, for example, the case in which the U.S. Supreme Court upheld field sobriety checkpoints, as long as they are conducted according to specific guidelines. When that case was returned to the state level for further action, the Michigan Supreme Court ultimately concluded that such checkpoints violate the state constitution.
Michigan is not alone in this prohibition. Ten other states ban sobriety checkpoints.
Though Connecticut is not one of those, it's clear that implementation of DUI checkpoints here has to be done according to established guidelines.
As we've discussed, one component of the guidelines is to publicize them widely in advance. The National Highway Traffic Safety Administration has issued instructions to law enforcement agencies on this point.
Source: "Why do Police Announce DUI Checkpoints?" Valley Independent Sentinel, Ethan Fry, 11-20-12
Our firm handles situations similar to those discussed in this post. To learn more about our practice, please visit our Connecticut DUI defense page.