Supreme Court: Cops Need Warrants for DUI Blood Tests

Supreme Court: Cops Need Warrants for DUI Blood Tests

By Victoria Kim 04/17/13

Warrantless blood-testing of DUI suspects is ruled unconstitutional.

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Police must obtain a warrant to draw blood.
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The Supreme Court ruled today that cops must obtain a search warrant before blood-testing DUI suspects—a murky area of the law that the The Fix wrote about previously in Texas. The test case began with the arrest of one Tyler McNeely in rural Missouri, whose "speeding, swerving" car was pulled over by the Missouri State Highway Patrol. McNeely, who had two previous drunk-driving convictions, was arrested after failing a field sobriety test and refusing a breathalyzer. McNeely was taken to a hospital, where a technician performed a blood test without his consent. It showed a blood alcohol level of 0.15, almost twice the legal limit. The Missouri Supreme Court upheld a lower court's decision to suppress the evidence, finding there had been no "exigent circumstances" that excused the failure to obtain a warrant, and that the warrantless blood test violated the Constitution's protection against unreasonable searches and seizures. Today, Supreme Court Justice Sonia Sotomayor wrote that the dissipation of blood alcohol over time is not sufficient reason to allow police to take a blood sample without first seeking a judge's approval. Eight of the nine justices sided with McNeely, agreeing that a warrantless blood test violates constitutional rights. Only Justice Clarence Thomas dissented: "Because the body's natural metabolization of alcohol inevitably destroys evidence of the crime," he said, "it constitutes an exigent circumstance." Missouri and the Obama administration wanted the court to allow warrantless blood-testing. About half the states already prohibit warrantless blood tests in all or most DUI cases.