The Fourth Amendment of the U.S. Constitution provides that we should be free from unreasonable searches and seizures. The U.S. Supreme Court recently issued a decision in a case involving the intersection of the Fourth Amendment and individuals suspected of driving under the influence of alcohol.

Missouri v. McNeely – the case before the high court – involved a man who was stopped by a law enforcement officer for a traffic violation. During the traffic stop, the police officer suspected that the driver was under the influence of alcohol. The driver did not pass a round of field sobriety tests. He also did not agree to submit to a breathalyzer.

The driver was arrested. Instead of taking him to jail, the police officer stopped at a hospital. Although the motorist did not give permission, the officer asked a medical professional at the hospital to draw his blood.

Throughout the process, the police officer did not attempt to obtain a warrant for the blood draw. He later explained that he did not think he was required to get a warrant under the circumstances.

The state of Missouri asked the U.S. Supreme Court to find that warrants are not required in such cases because alcohol dissipates in the blood over time. Consequently, the attorneys argued, time was of the essence in cases of suspected DUI and waiting for a warrant would jeopardize the evidence.

The high court did not agree with the state’s argument. Instead, Justice Sotomayor wrote that law enforcement officers must attempt to obtain a warrant in cases where doing so would not “undermine the efficacy of the search.”

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