Warrantless blood draws–can police do them?

When police investigate suspects for DWI, they utilize a variety of measures to gather every piece of evidence they can. In some cases, this means taking blood samples from a DWI suspect. Blood samples, to be sure, are rather invasive for suspects, and police have to have good grounds to perform them.

To be specific, police must generally have a search warrant before taking blood samples in DWI investigations. This, in fact, is a constitutional requirement clarified by the Supreme Court in 2013. In the McNeely case, the Supreme Court specifically held that police officers do not have the authority to forego obtaining a search warrant just because they are worried about the natural dissipation of alcohol in the suspect’s bloodstream.

In McNeely, the Supreme Court held that several factors must be considered when determining whether officers have authority to forego a warrant before making a blood draw. In fact, the Supreme Court recently refused to hear a Colorado appeal which sought greater clarity on the issue. The state had apparently argued that a warrant should not be required in cases where police do not have enough time to obtain one before the suspect’s blood alcohol level dissipates.

The court apparently determined that the issue is not worth consideration. So, as of now, the 2013 decision remains the rule: police must consider several factors rather than just natural dissipation of alcohol when determining whether to obtain a warrant.

Search and seizure law is an important area for DWI suspects to explore with their criminal defense attorney. Doing so ensures that a defendant is able to prevent prosecutors from basing their case on substandard or questionable police work.

Source: Beaumont Enterprise.com, “Supreme Court won’t hear dispute over DUI blood tests,” January 12, 2015.

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