A three-judge panel of the U.S. Court of Appeals for the Fourth Circuit (Richmond) today ruled that a warrant is generally necessary before law enforcement officials can obtain historical cell site location information, although it said evidence in a case before it was admissible because the government relied on court orders issued under the Electronic Communications Privacy Act.

“We conclude that the government’s warrantless procurement of the CSLI [cell site location information] was an unreasonable search in violation of Appellants’ Fourth Amendment rights,” the court said. “Nevertheless, because the government relied in good faith on court orders issued in accordance with Title II of the Electronic Communications Privacy Act, or the Stored Communications Act (‘SCA’), we hold the court’s admission of the challenged evidence must be sustained.”

In the investigations that gave rise to “U.S. v. Aaron Graham and Eric Jordan” (cases 12-4659 and 12-4825), police obtained 221 days’ worth of historic cell phone location data for two suspects in six armed robberies in the city of Baltimore and in Baltimore County, Md.

The opinion was written by Senior Judge Andre M. Davis. Judge Stephanie D. Thacker joined in the opinion and wrote a separate concurring opinion. Judge Diana Gribbon Motz wrote an opinion dissenting in part but concurring in the judgment.

Civil liberties advocates welcomed today’s ruling and said it could increase the chance that the U.S. Supreme Court will consider the issue, noting that the Fifth and Eleventh circuits have ruled that warrants aren’t necessary to obtain cell phone location information.

“Today’s opinion is a full-throated defense of Fourth Amendment privacy rights in the digital age. Cell phone location records can reveal some of the most private details about our lives by showing where we go and who we spend time with,” said Nathan Freed Wessler, staff attorney with the American Civil Liberties Union’s Speech, Privacy, and Technology Project. “Requiring a warrant for access to this information is an important protection against unjustified government intrusions.”

“Of course the Fourth Amendment should apply to our location data. We take our cell phones with us everywhere and they can reveal the most private aspects of our lives—not only our daily routines, but also friendships, visits to medical clinics, and participation in protests. The court was right in ruling that law enforcement needs a warrant to access this deeply personal information,” said Greg Nojeim, director of the Center for Democracy & Technology’s Freedom, Security, and Technology Project. —Paul Kirby, paul.kirby@wolterskluwer.com