The Georgia Supreme Court just waded into this legal conundrum, ruling that consent obtained with a stick isn’t necessarily free and voluntary. In the short run, the decision is likely to keep Georgia judges busy fielding warrant applications in DUI cases. In the long run, it could upend decades of standard practice in impaired driving cases nationwide.

“This could be a huge decision,” said Shea Denning, a lawyer and professor of government at the University of North Carolina who specializes in motor vehicle law.

Which doesn’t mean that many people saw it coming. They didn’t.

“Some lawyers and judges looked at me cross-eyed. They said I was crazy,” said Lance Tyler, the Gwinnett County DUI lawyer who filed the lawsuit that yielded the ruling.

Since the 1960s, most states, including Georgia, have had laws on the books that say anyone who drives on public roads has given “implied consent” to being tested for drugs or alcohol if a cop has probable cause to believe they’re driving under the influence. Georgia’s law, like most others, allows a suspect to refuse, but on penalty of losing his license for a year.

However, the Constitution’s guarantee against “unreasonable searches and seizures” demands something rather different. Courts have held that cops can’t search either your home or your body without a warrant, except in certain well defined circumstances, one being that you “freely and voluntarily” consent to the search.

It’s only in recent years that courts have begun to address the tension between the Constitution and the state laws. Last week, Georgia’s high court ruled that a lower court was wrong to assume that a suspect who submits to the required test under state law has consented to waive the constitutional requirement for a warrant. The justices sent the case back to the lower court to directly address that issue.

The upshot is that, for the time being, there are likely to be a whole lot more cops seeking warrants to draw blood from DUI suspects. And that represents a fundamental shift, if not an insurmountable hurdle.

“Implied consent is a linchpin to enforcement of impaired driving laws everywhere,” Denning said. “If those laws are constitutionally infirm, that would have a huge impact.”

Frank Rotondo, executive director of the Georgia Association of Chiefs of Police, said that, whatever the legal outcome, cops will adjust however they must to legally get impaired drivers off the road.

“All decisions that seem not to favor law enforcement make us get better and make cases tighter,” Rotondo said, drawing a parallel to the court-mandated “Miranda” warnings that have become a reflexive part of police procedure.

Depending on how the legal process plays out from here, he said, the Legislature might amend Georgia’s implied consent law, or law enforcement officials might re-write the standardized script cops use to inform suspects of their obligations and rights during DUI stops.

If the law must be rewritten to conform to a changing legal landscape, it will hardly be the first time.

In 2005, the Georgia Supreme Court ruled that the state’s implied consent law was written in such a way that if a suspect refused a blood test, the cop was barred from seeking a search warrant to override the refusal. The Legislature fixed that problem the next year by amending the law.

And even if the end result of the recent ruling is that warrants are required in most DUI cases, we live in an era of electronic communications, Rotondo noted. Various jurisdictions could set up systems in which on-call judges issue electronic warrants in response to electronic applications from patrol officers in the field.

A spokeswoman for the Atlanta Police Department said APD officers already have access to an electronic warrant system.

“Law enforcement has to be resilient,” and that’s nothing new, Rotondo said.

The driver at the center of the current case, John Cletus Williams, was arrested in 2012 by Gwinnett County Police on suspicion of driving under the influence. (He was found to have very high concentrations of a narcotic painkiller, a tranquilizer and a muscle relaxant in his blood.)

The officer read Williams the standard script, saying that if he refused a blood test, he would lose his license for a year, among other penalties. He told Williams it was a “yes or no question,” and Williams said yes.

But Tyler argued in his lawsuit that even though Williams agreed to comply with Georgia’s state law, he had not waived his right under the Fourth Amendment to the Constitution to be free of unreasonable searches and seizures.

The Georgia court’s action marks the second time in two years that courts have significantly narrowed the circumstances in which police can obtain blood samples from people suspected of driving while impaired by drugs or alcohol.

For decades, police had relied on another exception to the Constitution’s rule about search warrants, one that allows cops to forego a warrant in emergency situations. In a 1966 case, the U.S. Supreme Court said that a DUI stop could be considered a de facto emergency, because alcohol breaks down rather quickly in the bloodstream. Every minute the cops spent in getting a warrant was a minute during which evidence of a potential crime was being metabolized away.

From then on, it was widely assumed that all DUI stops were emergencies under the Fourth Amendment. Then, in 2013, the Supreme Court said its earlier ruling had been interpreted too broadly. It said biochemistry doesn’t automatically override constitutional protections — that a warrant is still necessary to draw blood unless police can show some other reason for treating a given DUI stop as an emergency.

Even then, things didn’t change much in Georgia, because DUI suspects faced the choice of losing their licenses or having their blood tested. When they said yes to the test, that was treated as a waiver of their constitutional right not to be searched without a warrant.

Until now.

Where things go from here is something of a puzzle, Denning said. What facts shall the lower court rely on in its reconsideration whether Williams gave free and voluntary consent to a blood test? If they ask him, there’s little doubt what he’d say.

Even Tyler, the man who set it all in motion, said he’s a little flummoxed by what he’s wrought.

“I’ve wondered many times,” he said, “what happens if I win?”