The Supreme Court has accepted a challenge to the warrantless collection of historical cellphone location data in a case that could curtail U.S. government surveillance and expand American privacy rights.

The case, Carpenter v. U.S., was granted certiorari Monday on appeal from the U.S. Court of Appeals for the 6th Circuit, which found that police did not need a warrant based on probable cause to collect 127 days of cellphone records from MetroPCS and Sprint.

Timothy Carpenter was found guilty of participating in six Michigan robberies after the government said those cellphone records – which included calls made and geographic location – placed him near four of the crime scenes. He is serving a 116-year prison sentence.

Federal courts have provided mixed rulings on whether the Fourth Amendment requires police to get a warrant. Authorities say a warrant is not necessary in Carpenter's case, as the Supreme Court’s 1979 ruling in Smith v. Maryland holds that people have no expectation of privacy over information voluntarily given to companies.

The so-called third party doctrine of Smith v. Maryland, which dealt with a short span of landline records, and related cases also applies to some banking and internet records. It has been used to justify mass surveillance by the federal government, including the National Security Agency’s now-curbed dragnet of U.S. call records.

Harold Gurewitz, one of Carpenter’s attorneys, says “it is certainly time for the court to review the prior cases that have been relied upon in our case.”

“I think it is extremely important because of the overwhelming presence of cellphones in the lives of Americans,” he says.

Nathan Freed Wessler, an attorney for the American Civil Liberties Union who has been directly involved in many of the lower-court fights on historical location data, also is representing Carpenter.

“The vast majority of Americans carry cellphones with them in their everyday lives, and the question posed by this case is whether the traditional protections of the Fourth Amendment – including a warrant – will apply to prevent the pervasive location-tracking of any one of us,” Wessler says.

Privacy advocates may have reason for optimism. The Supreme Court in 2014 ruled that police generally need to get a warrant to search the cellphones of people who have been arrested. In 2012, the high court ruled in Jones v. U.S. that police needed a warrant to attach a tracking device to a car.

Justice Department attorneys argue in a brief, however, that those cases do not support Carpenter's position.

"[Carpenter] essentially seeks a rule that he has a personal Fourth Amendment interest in the record of his transaction with a business from which his location can be approximately inferred. No recognized Fourth Amendment doctrine supports that contention," the Justice Department said.

Though some authorities do seek warrants for cellphone location records, they also can get a court order using a lower legal standard under the Stored Communications Act by saying the information is relevant to an investigation – as was done in Carpenter's case – or obtain records voluntarily by citing an emergency.

Wessler says the court's ruling could have expanded effects, potentially influencing police use of devices known as Stingrays that collect real-time cellphone location data and toppling a legal pillar used to justify broad surveillance.