The U.S. Supreme Court on Wednesday sided with a Jackson man who claimed his Fourth Amendment rights were violated when a state trooper required him to undergo a blood test after a 2010 traffic stop.

Tyler McNeely already had two prior drunk-driving convictions when Cpl. Mark Winder of the Missouri State Highway Patrol pulled him over in Cape Girardeau County. McNeely failed field sobriety tests and refused a breathalyzer test, so Winder took him to Saint Francis Medical Center in Cape Girardeau and ordered a blood test.

The Missouri Supreme Court ruled in January 2012 that because the test was done without either McNeely's consent or a search warrant, it violated his constitutional rights.

The U.S. Supreme Court upheld that ruling 8-1, with Justice Clarence Thomas the lone dissenter.

Justice Sonia Sotomayor, writing for the court, said the natural dissipation of alcohol in the bloodstream does not constitute an emergency that justifies a warrantless search.

"In those drunk-driving investigations where police officers can reasonably obtain a warrant before a blood sample can be drawn without significantly undermining the efficacy of the search, the Fourth Amendment mandates that they do so," Sotomayor wrote.

Jack Koester, assistant prosecuting attorney for Cape Girardeau County, was disappointed with the outcome of the case but said he respects the court's decision.

Koester said the court's response leaves little guidance for police officers, who have to decide whether a given case merits a warrantless blood test.

"You have to show in a particular case that a search warrant could not be obtained expeditiously. The problem, though, is how do you define 'expeditiously'?" he said. "It does not give any meaningful guidance to police officers."

In his dissenting opinion, Thomas noted that a suspect's blood alcohol content -- a key piece of evidence in drunk-driving cases -- diminishes over time.

"Nothing in the Fourth Amendment requires officers to allow evidence essential to enforcement of drunk-driving laws to be destroyed while they wait for a warrant to issue," Thomas wrote. "... Suspects' initial levels of intoxication and the time necessary to obtain warranted blood draws will vary widely from case to case. Even a slight delay may significantly affect probative value in borderline cases of suspects who are moderately intoxicated or suspects whose BAC is near a statutory threshold that triggers a more serious offense."

Concurring with some parts of the majority opinion while dissenting on others, Chief Justice John Roberts criticized the court for failing to provide specific guidance for officers in the field.

"The question presented is whether a warrantless blood draw is permissible under the Fourth Amendment 'based upon the natural dissipation of alcohol in the bloodstream,'" Roberts wrote. "The majority answers 'It depends,' and so do I. The difference is that the majority offers no additional guidance, merely instructing courts and police officers to consider the totality of the circumstances."

In affirming the court's decision, Sotomayor cited the speed with which modern technology enables officers to obtain warrants; the invasive nature of blood sample collection; and the possibility for one officer to seek a warrant while another transports a suspect to the hospital, thus reducing the gap between the time of the arrest and the time blood is drawn.

"We are aware of no evidence indicating that restrictions on nonconsensual blood testing have compromised drunk-driving enforcement efforts in the States that have them," she wrote.

Tony Rothert, legal director for the American Civil Liberties Union of Eastern Missouri, was pleased with the decision.

"Our main concern was that if the case had gone another way, the Fourth Amendment would have had no application at all in drunk-driving cases. Police officers would have had unfettered discretion to force drivers to submit to a blood test in drunk-driving cases without consent and without a warrant," Rothert said. "Today's guidance, I think, is clear, and that is if there's a possibility of getting a warrant, you have to get a warrant."

Because of his prior convictions, McNeely still faces a Class D felony charge, which carries a penalty of up to four years in prison, Koester said. The ruling Wednesday means the blood test result is inadmissible in court, but prosecutors still can use other evidence, such as field sobriety tests and McNeely's refusal to submit to a breathalyzer, Koester said.

epriddy@semissourian.com

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