For the first time, a federal appeals court has ruled that law enforcement can’t obtain location data from cell phone providers without a warrant, in a decision that ACLU staff attorney Nathan Freed Wessler says reflects “a growing consensus for the need to limit surveillance.”

A three-judge panel for the 11th Circuit Court of Appeals in Florida ruled unanimously that police violated Quartavious Davis’s Fourth Amendment rights when they obtained location data from his cell phone provider and used it as evidence to convict him of 16 counts of robbery and other crimes.

Contending that “there is a reasonable privacy interest in being near the home of a lover, or a dispensary of medication, or a place of worship, or a house of ill repute,” the judges held “that cell site location information is within the subscriber’s reasonable expectation of privacy. The obtaining of that data without a warrant is a Fourth Amendment violation.”

While Wessler expressed disappointment that the panel didn’t reverse the actions of the lower court that originally heard Davis’s case and overturn an “unconscionable” 162-year sentence, he said, in a Thursday phone interview with SCMagazine.com, that the ruling “put police on notice, if you don’t have a warrant, your evidence is going to get thrown out.”

Davis was charged with a string of robberies as well as conspiracy to commit robbery and possession and use of a firearm in commission of a violent crime. Eyewitness testimony, as well as that from co-conspirators, put him at the scenes of some of the crimes and other evidence supported the case against him. But the prosecution presented wireless carrier location data, spanning a 67-day period, to bolster their case and show that Davis was in the vicinity of many of the locations when the crimes were committed.

Prosecutors countered Davis’s eventual appeal, explaining to the court that they had obtained the data under a D-order from a federal magistrate judge as specified by the Stored Communications Act where the standard is “relevant and material” rather than the higher “probable cause” standard under the Fourth Amendment.

Five others were indicted as well and law enforcement tapped location data on some of them during the same period. But the appeals court rejected that argument and instead delivered what Electronic Frontier Foundation Senior Staff Attorney Hanni Fakhoury told SCMagazine.com, is an “important decision” that can be “read broadly” to include not only stored data but real-time information as well.

Courts at the federal level have shied away from directly addressing the parameters of privacy protection under the Fourth Amendment as it relates to location data. In a few high-profile cases, one notably argued before the Supreme Court, judges have skirted the privacy issue and have remained on more familiar and firm Constitutional turf — addressing the clear protection against trespass offered by the amendment.

But the 11th Circuit Court’s decision is in line with lower court leanings in several states, including New Jersey, where the rulings have been decidedly — and pointedly — in favor of clipping law enforcement’s wings and holding them to a Fourth Amendment privacy standard.

“There is a growing concern among courts and legislators about allowing police to gain access [without a warrant],” Fakhoury said, noting that this recent decision, which comes just days after a Florida judge sided with the ACLU over unsealing documents related to law enforcement’s use of stingray devices, is encouraging considering that the 11th Circuit is “not exactly considered a liberal bastion.”

While the ruling applies to the jurisdiction of the 11th Circuit, which includes Florida, Georgia and Alabama, both Wessler, who argued the case as a friend-of-the-court in April, and Fakhoury expect it to have broader implications and lay the groundwork for future decisions — similar cases are currently pending in the 4th and 6th Circuit Courts — that will shape and clarify that privacy protection.

“It sets up some interesting (court) battles,” said Fakhoury, who noted that the ruling was “at odds with a decision by the 5th Circuit Court of Appeals. That discordance between the two rulings, “increases the likelihood that the Supreme Court will weigh in and resolve the split,” he explained, maybe even sooner than expected.