WASHINGTON - In an 8-1 decision Wednesday, the Supreme Court rejected Missouri prosecutors' contention that police should have the freedom to act quickly and dispense with a warrant because alcohol dissipates in the blood.
Instead, the court said it would hold fast to its view that the Fourth Amendment's ban on "unreasonable searches" means that authorities usually need a warrant from a magistrate before invading a person's privacy.
And sticking a needle into someone's veins "is an invasion of bodily integrity (that) implicates an individual's most personal anddeep-rooted expectations of privacy," said Justice Sonia Sotomayor.
But she also said that police sometimes need to act quickly, and in those cases they do not need to wait for a magistrate. For example, an officer might find it hard to obtain a warrant if a driver is arrested late at night in a rural area.
Still, these emergencies should be the exception, not the rule, Sotomayor said.
Wednesday's decision actually makes little change in the law regarding impaired drivers. In all 50 states, motorists who are stopped on suspicion of drunken driving must consent to a breath or blood test.
Tyler McNeely, a Missouri man, refused to undergo a breath test after he was stopped for speeding after midnight. Without obtaining a warrant, an officer took him in custody and drove him to a nearby hospital to have his blood drawn by a lab technician. It showed that McNeely was intoxicated.
But the Missouri courts threw out the evidence on the grounds that the forced blood test was unconstitutional without a warrant.
In their appeal to the Supreme Court, the state attorneys sought a big win. Rather than argue narrowly that the officer who arrested McNeely had a special need to act fast because it was the middle of the night, the state's attorney asked the justices to rule that search warrants are never required for blood-alcohol tests.
That proved to be a tactical mistake.
"We hold that in drunk-driving investigations, the natural dissipation of the blood does not constitute an emergency in every case sufficient to justify conducting a blood test without a warrant," Sotomayor said.
Justice Clarence Thomas dissented alone. "Because the body's natural metabolization of alcohol inevitably destroys evidence of the crime, it constitutes an exigent circumstance" to bypass a warrant, he said.
The ruling might not affect Idaho drivers under the implied consent law.
It's likely to take a few Idaho legal challenges over drawing blood without a warrant before law enforcement gets a clear picture of what officers may or may not do, says an Idaho expert.
Normally a search - including a blood sample - requires a judge to approve a warrant, under the U.S. Constitution's guarantee against warrantless search or seizure.
Jared Olson, a traffic safety resources prosecutor with the Idaho Prosecuting Attorneys Association, said Idaho recognizes two exceptions to the requirement for a warrant before drawing blood from a suspect.
One requires an emergency situation. The U.S. Supreme Court's decision Wednesday focused on the emergency exception, when authorities argue they need a blood test before alcohol is metabolized into the body. The court said metabolism isn't sufficient grounds for a warrantless blood draw.
The second exception - and vital one - is the state's implied consent law, under which motorists who want to drive Idaho roads essentially give their consent for a breath, urine or blood test, said Olson.
Though the court didn't emphasize implied consent in its opinion, Olson said the court's ruling could raise questions about Idaho's exception for taking blood without getting a judge's approval.
Those questions would have to be tested by future court cases.
Bill Roberts: 377-6408