HARRISBURG, Pa. (AP) — Police must have probable cause as well as “exigent circumstances” in order to legally search a vehicle without a warrant, a divided Pennsylvania Supreme Court ruled Tuesday.

The 4-3 decision said the state constitution's privacy protections are greater than the U.S. Constitution's and that those protections extend to vehicles. The court overruled its own 2014 decision that probable cause alone was sufficient, given that vehicles are inherently mobile.

“Difficulties in clarifying the scope of the exigency requirement will lead to debates about what exactly the Pennsylvania Constitution demands in a given situation. But so what?” wrote Justice Christine Donohue, referring to the state's constitutional language on searches.

“The long history of Article I, Section 8 and its heightened privacy protections do not permit us to carry forward a bright-line rule that gives short shrift to citizens’ privacy rights," Donohue wrote for the majority.

Exigent circumstances might include a belief that people are in danger or that important evidence is about to disappear. Donohue said “the universe of qualifying ‘exigent circumstances’ is impossible to define with precision,” but they must go beyond that vehicles have wheels and can be driven away.

Greg Rowe with the Pennsylvania District Attorneys Association said the existence of “exigent circumstances” in warrantless searches will be made on a case-by-case basis.

“Based on our initial review, we believe this decision will dramatically change the legal interpretation of how warrantless searches of automobiles are conducted in Pennsylvania and could greatly diminish the clarity and predictability in this area of the law,” Rowe said.

In a 2011 search warrant case that did not involve a vehicle, the U.S. Supreme Court listed as exigent circumstances the need to provide emergency aid, hot pursuit of a fleeing suspect or the prospect of the destruction of evidence.

Donohue's opinion was joined by three of the other four Democrats on the court. Both Republican justices and Democratic Justice Kevin Dougherty dissented, arguing the 2014 precedent should stand.

“When we become untethered from our previous decisions, we instantly implicate this court’s credibility and our ability to effectively adjudicate the many types of cases upon which litigants look to us for guidance,” wrote Republican Justice Sallie Mundy.

She said the previous standard of probable cause alone to justify a warrantless vehicle search “offered a bright-line rule already in effect" and “deferred to the needs of those we entrust with the difficult job of policing.”

The court sent the Philadelphia case that prompted the decision back to county court to more fully examine whether exigent circumstances existed.

In that case, the defendant had been convicted of possession of heroin with intent to deliver after a 2016 vehicle stop in which drugs were recovered from a locked metal box inside the vehicle he had been driving.