Updated

Federal agents can obtain cellphone records that reveal a caller’s location without a warrant, a Cincinnati-based federal appeals court said on Wednesday in the latest ruling to tackle the scope of privacy protections for data transmitted by personal devices.

The records obtained by the Federal Bureau of Investigation from wireless carriers in 2011 showed that two Detroit men were near the scene of several robberies at the time they were committed. Timothy Carpenter and Timothy Sanders, who were ultimately convicted of participation in nine armed robberies, sought to exclude the records, saying they were protected by the Fourth Amendment.

A 2-1 panel of the Sixth U.S. Circuit Court of Appeals ruled that location records created when a mobile phone connects to a nearby cell tower were the equivalent of the writing on the outside of an envelope, rather than the letter inside.

“Cell-site data—like mailing addresses, phone numbers, and IP addresses—are information that facilitate personal communications, rather than part of the content of those communications themselves,” wrote Judge Raymond Kethledge. “The government’s collection of business records containing these data therefore is not a search.”

Harold Gurewitz, a lawyer for Mr. Carpenter, said he and his client were considering their next move. They could ask the Sixth Circuit to rehear the case or petition the U.S. Supreme Court to review it. Until the high court steps in, Mr. Gurewitz said, “I think the issue is just going to be unclear.”

The ruling aligns the Sixth Circuit with two other regional appeals courts and means that law enforcement officers in Kentucky, Michigan, Ohio and Tennessee can obtain a court order for location data by showing merely that the records are relevant to an ongoing investigation. A warrant requires a showing of probable cause.

A three-judge panel of a fourth federal appeals court ruled in August that police need a warrant to obtain such records. That ruling is under review by the full court.

In recent years, the U.S. Supreme Court has erred on the side of privacy in disputes over whether the Fourth Amendment protects against the installation of a global positioning system tracker on a suspect’s vehicle or a search of his phone during an arrest.

The cell records obtained by the FBI showed that Mr. Carpenter and his half- brother, Mr. Sanders, were nearby the scene of four robberies in Warren, Ohio, and Detroit in 2010 and 2011.

Mr. Carpenter was sentenced to more than 116 years in prison, while Mr. Sanders was sentenced to about 14 years.

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