Yesterday, the Supreme Court announced that it will hear a case with significant ramifications for privacy in the digital age. The case involves a man convicted of armed robbery based in part on cellphone location data obtained without a probable cause warrant. The conviction was appealed at the Sixth Circuit Court of Appeals, which held that the Fourth Amendment does not require a warrant under such circumstances.

While the Supreme Court has recently restricted the search of cellphone contents and the use of GPS devices by law enforcement, it ruled in 1979 that a robbery suspect had no reasonable expectation of privacy in numbers dialed from his phone because the suspect had voluntarily turned this information to the phone company. Relying on this “third-party doctrine,” federal appeals courts have generally agreed that the Fourth Amendment does not protect cellphone location data because customers routinely provide this data to cellphone companies.

Cellphone carriers can track individuals’ approximate locations based on which signal towers the cellphone can reach, and law enforcement officials frequently obtain such information to assist in investigations. This case, likely to be heard in the fall, gives the Supreme Court an opportunity in the digital age to clarify privacy rights in such records.