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Can Police Force a Blood Draw in a DUI Stop Without a Warrant?


To lead into today’s post topic, we’d like our Dublin readers to first consider this scenario: a driver has just been pulled over by a California police officer who suspects the driver is under the influence of alcohol. The officer asks the driver to submit to a breath test but the driver refuses.

The officer knows that if he doesn’t get a blood-alcohol reading soon, he might not be able to prove his suspicion that the driver is over the legal limit. Instead of waiting for a warrant, the officer believes that he has reason enough to force the blood draw without the driver’s consent because of alcohol burn off and the need for an accurate reading.

It’s because of a situation such as this that we’re asking the question above: can police force a blood draw in a DUI stop without a warrant? Many people, including a large majority of our Dublin readers, have probably heard of a situation such as this occurring. Many more have probably heard the excuse used by the officer in this scenario. But do such grounds exist or is forcing a blood draw without a warrant illegal?

This very question was posed to the U.S. Supreme Court two years ago in the case of Missouri v. McNeely as well as by a number of other cases across the nation. Confusion lie in how states should interpret their own drunk-driving laws in accordance with a person’s Fourth Amendment rights. It was presumed by some that the metabolization of alcohol should qualify as an exemption to the warrant requirement. Others disagreed, which is why the case was finally heard by the U.S. Supreme Court.

In a 5-4 decision, the high court upheld the decision to enforce warrants on blood draws during DUI stops and arrests. As Justice Roberts explained, “If there is time to secure a warrant before blood can be drawn, the police must seek one.” Many of the judges agreed too that metabolization of alcohol was not an emergency enough to allow a warrantless blood draw.

What this means for our scenario above is that the officer could be violating the driver’s civil rights if a warrantless blood draw is pursued. Doing so could make the blood draw inadmissible in any future criminal proceedings. The driver might not know this though unless they talk to a criminal defense attorney.

Sources: The Washington Post, “Supreme Court limits warrantless blood tests for drunken driving suspects,” Robert Barnes, April 17, 2013

The SCOTUS Blog, “Missouri v. McNeely,” Accessed July 27, 2015