Photographer: Andrew Harrer/Bloomberg

Supreme Court Justices Hint at More Digital-Privacy Protections

Updated on
  • Supreme Court considers case over cell-phone location data
  • Court may split along unusual lines on warrant requirement

U.S. Supreme Court justices hinted they may curb the power of law enforcement officials to track people using mobile-phone data, expressing concern about privacy intrusions in the digital age.

In a spirited argument that went 20 minutes beyond its scheduled hour Wednesday, the justices considered requiring prosecutors to get a warrant before obtaining mobile-phone tower records that show a person’s location over the course of weeks or months.

"This is highly personal information," Justice Stephen Breyer said.

The case could have a far-reaching impact. Prosecutors seek phone-location information from telecommunications companies in tens of thousands of cases a year. More broadly, the court’s decision will help set the rules governing government access to the fast-growing trove of information available on the cloud, including data from virtual assistants, smart thermostats and fitness trackers.

Several justices, including Sonia Sotomayor and Elena Kagan, indicated they were concerned about the increasing precision of the phone location data being kept by wireless providers.

"A cell phone can be pinged in your bedroom," Sotomayor 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."

Unusual Divisions

But Justices Samuel Alito and Anthony Kennedy questioned whether location data was any more sensitive than bank records, which the court said in 1976 aren’t protected by the Constitution’s Fourth Amendment because they are in possession of the financial institution.

"Your whereabouts are publicly known," Kennedy said. "People can see you. Surveillance officers can follow you. It seems to me that this is much less private" than bank records.

The session indicated the court might divide along unusual lines. Two of the court’s conservatives, Chief Justice John Roberts and Justice Neil Gorsuch, joined Breyer, Sotomayor and Kagan in suggesting they might vote to impose stronger privacy protections. Justice Ruth Bader Ginsburg directed most of her questions at the American Civil Liberties Union lawyer who was arguing for broad privacy rights.

The case involves Timothy Ivory Carpenter, who is seeking to overturn his conviction for taking part in a string of armed robberies of Detroit-area Radio Shacks and, ironically, stores for wireless provider T-Mobile US Inc.

Months of Data

At trial, prosecutors used four months of data obtained from Carpenter’s wireless carriers to show he was within a half-mile to two miles of the location of four of the robberies when they occurred. Mobile-phone companies typically keep records that show the cell sites where their customers’ calls begin and end.

Prosecutors in most of the country can get that data without a warrant through the 1986 Stored Communications Act. That law says prosecutors need only have "reasonable grounds" to believe the information would be useful in an investigation. A court warrant would require a stronger showing of "probable cause."

Carpenter’s lawyers said they were seeking a limited ruling that would require a warrant if location data covered longer than a 24-hour period. Collecting that information "disturbs people’s long-standing, practical expectation that their longer-term movements in public and private spaces will remain private," said Nathan Wessler, the ACLU lawyer representing Carpenter.

Ginsburg was among the justices who questioned whether the 24-hour cutoff made any practical sense.

"So, if there were only one robbery, we could get that information, but now there are how many -- eight?" she asked. "So we can’t get it for eight, but we can get it for the one?"

The Justice Department says a federal appeals court was right to uphold Carpenter’s conviction. Deputy Solicitor General Michael Dreeben pointed to the Supreme Court’s 1979 Smith v. Maryland decision, which said the phone numbers a person dials aren’t constitutionally protected because the caller has already provided them to a third party -- that is, the phone company.

The government "is asking a business to provide information about the business’s own transactions with a customer," Dreeben said. Dreeben, a veteran Supreme Court advocate, was making his first argument since taking on an additional assignment as part of Special Counsel Robert Mueller’s team investigating possible collusion between Russia and President Donald Trump’s campaign.

Bedroom Phones

Roberts questioned Dreeben’s contention that consumers are voluntarily providing location information to their phone companies. The chief justice said that argument was "inconsistent" with an opinion he wrote in 2014, when the court said police generally must get a warrant before searching the phone of someone who is being arrested.

That ruling "emphasized that you really don’t have a choice these days if you want to have a cell phone," Roberts said.

Gorsuch signaled he might provide a unique take on the case, repeatedly asking the lawyers whether the government might be infringing the property rights of phone users.

The argument offered a few glimpses into the justices’ relative familiarity with modern technology, and their personal habits. Kennedy scoffed at the suggestion that consumers don’t know that their telecommunications providers collect phone data.

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

Sotomayor suggested her own cell phone use was more limited that that of people from a different generation.

"I don’t, but I know that most young people have the phones in the bed with them," she said. "I know people who take phones into public restrooms. They take them with them everywhere. It’s an appendage now for some people."

The court will rule by June in the case, Carpenter v. United States, 16-402.

    Before it's here, it's on the Bloomberg Terminal.