I’m Attorney Mike Contant. Here’s a question we frequently get asked when people talk to us about a drunk driving case, “Can the police draw my blood? And under what circumstances?” In Massachusetts, there are only two circumstances where the police get to draw your blood. 

A Search Warrant

The first is that they get a search warrant. A search warrant is a document issued by the courts. The police would have to go seek a clerk magistrate or a judge and provide them with enough information, usually in an affidavit, to establish probable cause. They need to convince them that they’re going to find evidence of a crime by taking your blood. 

This is rare in a drunk driving case. Still, the police can take this step to go ahead and get a search warrant for your blood. That’s one way they can force a blood draw. 

Your Consent

The second way is if you actually consent when they ask for your consent or when they ask you to sign a consent form saying that a medical representative is authorized to take your blood. 

Under these circumstances, many people are afraid and they don’t realize that they do not have to give their consent. They have every right to say, “No. You cannot take my blood. I am not consenting.” And that is our advice. You should always say, “No. I don’t want to consent to this blood draw.” 

A Third Way The Prosecution Can Get A Sample

In many cases involving drunk driving, there’s a third way that the prosecution can get a blood sample. This is where you were in an accident and were injured or otherwise brought to the hospital as a result of some medical complaint following your arrest. 

What happens at the hospital is that they will often take blood to determine how to diagnose you and how to treat you. Now, keep in mind that this isn’t the police doing this. It’s the hospital personnel, and it’s done as a means of treating you. 

Unfortunately, what happens in these cases is that the prosecutor, once you’ve been brought before the court, will learn that you went to the hospital because the police wrote it in their report and they’ll subpoena those records from the hospital to get your blood test to try to use it against you in that drunk driving matter. 

This happens quite often. And, unfortunately, it’s not the police doing it. Because the police, like I said, can only do it in one of two ways. One is if they have a warrant. And two is if you consent. 

If You Have Questions

If you have any questions about when the police have the right to draw your blood, about drunk driving or about anything related to the criminal process, please feel free to give me a call or shoot me an email. I’d be happy to speak with you about it.