The U.S. Supreme Court ruled Thursday that it is not unconstitutional for the breath of suspected drunken drivers to be tested without a search warrant, but maintained blood tests still require one, in an opinion that both upholds and overturns previous Minnesota court rulings.

The ruling remained largely silent about urine tests, setting the stage for further legal battles in the yearslong debate over the state's Implied Consent Law.

Minnesota's law makes it a crime for suspected drunken drivers to refuse a breath test, which the high court ruled Thursday is permissible under the Fourth Amendment, reasoning that breath testing is less intrusive than blood testing. A Minnesota case, State v. Bernard, was one of three challenges the justices heard on the subject, and Minnesota appellate courts previously ruled that no warrants were needed for either blood or breath testing in suspected DWI cases.

Officers approached William Bernard Jr., of Eagan, at a public boat ramp in 2012 and asked him to consent to sobriety tests, saying he smelled of alcohol. He declined and was arrested, which led to felony charges for refusal to submit to chemical testing. With Thursday's ruling, Bernard's case is scheduled to return to trial in Dakota County.

"This is the decision that nobody wanted," said Jeffrey Sheridan, an attorney who represents Bernard at the state level. "All this has done is muddy the waters and say one of these [tests] is subject to arrests and another is not."

Drivers in each state can have their licenses revoked for refusing to provide samples of breath, blood or urine. The court's ruling affects laws in 11 states that impose additional criminal penalties for such refusals. In 2014, the most recent year for which data is available, there were 25,258 impaired driving incidents in Minnesota, according to the Department of Public Safety. Of those, 15 percent involved test refusals.

"I think [Thursday's ruling] … will apply to someone every Minnesotan knows," said Charles Ramsay, an attorney for an Owatonna man whose 2012 refusal to submit to a urine test is now being reviewed by the Minnesota Supreme Court.

Writing for five justices in the majority, Justice Samuel Alito said breath tests do not implicate "significant privacy concerns." Unlike blood tests, Alito said breathing into a breathalyzer doesn't pierce the skin or leave a biological sample in the government's possession.

Daniel Koewler, a Minnesota attorney who helped argue the Supreme Court case, said he expects the high court's ruling on the invasiveness of blood testing to be a preview of how urine testing will be treated in Minnesota. "The privacy concern is incredibly exaggerated with urine tests," Koewler said.

In all three cases before the court, the challengers argued that warrantless searches should be allowed only in "extraordinary circumstances." They said routine drunken driving stops count as ordinary law enforcement functions where traditional privacy rights should apply.

Justices Sonia Sotomayor and Ruth Bader Ginsburg said they would have required search warrants for both breath and blood alcohol tests. Justice Clarence Thomas dissented, saying he would have found both tests constitutional.

"They compromised," Sheridan said. "And the result is that they ruled that the Fourth Amendment covers potheads and addicts but it does not protect the social drinker."

State officials called the testing laws a legitimate condition on the privilege of using state roads. State prosecutors argued that it was too burdensome for police to obtain a warrant every time a driver refused a test because some rural areas have only one judge on call late at night or on weekends. They also expressed concern that even if police get a warrant, a driver can still refuse to take an alcohol test and face lesser charges for obstruction.

During oral argument, some of the justices pointed out that even in rural states police can call a magistrate and get a warrant over the phone in just a few minutes. The states garnered support from Mothers Against Drunk Driving, which argued that public safety is a compelling reason that justified the laws. But civil liberties groups said states can't criminalize the assertion of a constitutional right.

On Thursday, Dakota County Attorney James Backstrom called the ruling a "well-reasoned and appropriate approach to addressing one of nation's greatest dangers to public safety." Meanwhile, police in Eagan have already sought warrants for blood tests after the state Court of Appeals in October threw out a man's conviction for refusing a warrantless blood test, Police Chief Jim McDonald said.

Since then, McDonald said, the department has only needed warrants for blood tests about a dozen times and only one caused a delay of about 90 minutes.

"I may be a minority in my profession, but I think if you're going to be sticking a needle in someone's arm and drawing blood out of it, you need a warrant," McDonald said.

The Associated Press contributed to this report.