Members of the Supreme Court appeared troubled Wednesday that police can search cellphone location histories without a warrant, but struggled with where the line should be drawn on privacy in the digital age.

Justice Sonia Sotomayor said most Americans want to avoid a situation where the government can peer into every aspect of their lives, including their whereabouts. She asked whether the government really believes that police should be able to search location history without probable cause.

“Right now we're only talking about the cell sites records, but as I understand it, a cellphone can be pinged in your bedroom,” she said. “It can be pinged at your doctor's office. It can ping you in the most intimate details of your life. Presumably at some point even in a dressing room as you're undressing,” she said.

“So I am not beyond the belief that someday a provider could turn on my cellphone and listen to my conversations,” she said.

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The case, Carpenter v. U.S., centers on Timothy Carpenter, who is appealing his conviction for a string of armed robberies of Radio Shack and T-Mobile stores in Ohio and Michigan in 2010 and 2011.

Carpenter says the FBI violated his Fourth Amendment right against unreasonable search and seizure by obtaining a history of his cellphone location data without a warrant from his wireless carriers, MetroPCS and Sprint. The government then used that information at trial to convict him.

He was ultimately sentenced to 116 years in prison for the robberies, which he organized and supplied the guns for, according to accomplices who testified against him. They said Carpenter served as the lookout while robbers went into stores and ordered employees to fill bags with smartphones.

Little did he know that police would use cellphone technology to link him to the robberies.

The government argued Wednesday that it was well within its rights under the Stored Communications Act of 1986 to get a court order for the records. The law allows location data to be searched if the government can show reasonable grounds to believe it will be relevant to a criminal investigation.

The standard is higher to obtain a warrant, with law enforcement officers required to show there is probable cause to believe a crime has occurred.

Carpenter's attorney Nathan Wessler, of the American Civil Liberties Union (ACLU), argued that collection of this information is a search and "disturbs people's long-standing, practical expectation that their longer-term movements in public and private spaces will remain private."

But members of both the court’s conservative and liberal wings struggled with where to draw the line between short-term data that should be accessible without a warrant and long-term data that should require one.

Justice Anthony Kennedy, who is often the court's swing vote, said maybe longer-term data “is more corroborative perhaps of innocence.”

Wessler said if the government obtained a short period of data that showed or appeared to show an individuals’ involvement in a crime, then that data would give probable cause to obtain a warrant for more.

Deputy Solicitor General Michael Dreeben, however, argued that Carpenter lacked a legitimate expectation of privacy to begin with because he voluntarily turned the location information over to a third party by signing up for a cellphone.

He said the government simply asked the cellphone companies to function as witnesses and produce business records of their transactions with customers.

“Anyone who subscribes to a cellphone service will communicate that information to towers in order to receive calls. The cellphone companies get that information to operate the cell network,” Dreeben said.

“They choose to make their own business records of that information. It's not a government mandate,” he said.

But Chief Justice John Roberts said those records aren’t merely created by the business; it’s a “joint venture with the individual carrying the phone.”

“That person helps the company create the record by being there and sending out the pings or whatever,” he said.

Wessler argued that network technology has advanced remarkably since Carpenter’s data was collected. Not only is data gathered for phone calls, he said, but also text messages and app updates, making the locations more precise.

“I agree with you that new technology is raising very serious privacy concerns, but how much of existing precedent do you want us to overrule or declare obsolete?” Justice Samuel Alito asked.

MetroPCS produced 127 days worth of data points for every incoming and outgoing call Carpenter made, while Sprint provided seven days worth of data for towers Carpenter pinged in its roaming agreement with MetroPCS.

And law enforcement officials are requesting this type of data more frequently.

From July 2015 to June 2016, the ACLU said in briefs that AT&T received 75,302 requests for cellphone location information. Verizon received approximately 18,935 requests for cellphone location data in just the first half of 2016.

Technology companies, including Facebook and Apple, did not take a side in the case, but urged the court in an amicus brief to adapt the Fourth Amendment to the new reality that Internet-connected devices are part of everyday life.

“Doing so would reflect this Court’s consistent recognition that Fourth Amendment protections, governed as they are by reasonable expectations of privacy, must respond to changes in technology that implicate privacy,” they wrote.

The court ruled in 2012 that attaching a GPS device to a vehicle and tracking its movements constituted a search under the Fourth Amendment.

In that case, Alito wrote in a concurring judgment that “society’s expectation has been that law enforcement agents and others would not — and indeed, in the main, simply could not — secretly monitor and catalogue every single movement of an individual’s car for a very long period.”

But on Wednesday, Kennedy wasn't sure people have an expectation of privacy when it comes to cellphone location data.

He said it seems to him to be a normal expectation that cellphone companies have that data.

"If I know it, everybody does," he said.

A decision in the case is expected by June.

- This story was updated at 2:28 p.m.