New Bedford residents who drink and drive run the risk of being caught up in the net cast by police in sobriety checkpoints. These checkpoints are typically set up by the Massachusetts State Police (MSP) in conjunction with local authorities around the state.

Sobriety checkpoints are established at undisclosed locations usually within specified times. According to a former Massachusetts district attorney who now is a criminal defense lawyer, the authorities are only “required to announce the reasoning behind the sobriety checkpoint [and] what county and . . . day they will be setting up the checkpoint.”

Isn’t it illegal?

In some states, yes. In neighboring Rhode Island, the checkpoints have been deemed illegal under statutes or via an interpretation of the federal or state Constitution.

But that’s not the case here. Even though the Massachusetts Declaration of Rights, Article 14, and the Fourth Amendment of the U.S. Constitution state that police can’t stop civilians without reason, a 2009 decision of the Massachusetts Supreme Court ruled in favor of the checkpoints.

In Commonwealth vs. Robert Murphy, sobriety checkpoints were determined not to be illegal. The theory behind the argument is that there is a predetermined formula for which drivers get stopped, e.g., every fifth vehicle. Theoretically, this eliminates any presumed bias.

The MSP counters criticisms with the argument that the checkpoints provide an effective means of getting drunk drivers off the road.

Can I fight a checkpoint arrest?

Certainly — and you may prevail. When you are stopped, the officer will briefly engage you in order to assess your sobriety. Those in question may be asked to pull to the side for further evaluation and screening.

At that point, the cop may ask you to perform several field sobriety tests. Here is where the question of constitutional violations can arise. A skillful criminal defense attorney may be able to get your charges dropped if it can be proven that the police failed to follow proper guidelines.

Of course, it is always better to err on the side of caution and arrange for a sober ride home. But it should never be assumed that police and prosecutors have a strong case against you.