Cell Phone Privacy Rights

The majority, in a 5-4 opinion, required the government in most cases to obtain a warrant to get a cell phone user’s location data from phone providers because it is a search under the Fourth Amendment. The decision highlights modern-day concerns about how much personal information can be gleaned from such data.

The appeal comes from a defendant in a string of Michigan bank robberies, and is one of the more important cases of the term about protections against unlawful searches and seizures.

The Supreme Court has ruled that police typically need a search warrant before trying to track a person's past movements via their cell phone.

Chief Justice John Roberts joined the four justices appointed by Democratic presidents in the decision Friday, which continued an expansion by the Roberts court of privacy rights in a digital age.

The Justice Department under both the Obama and Trump administrations argued that no warrant is required for access to cell-phone location information, because the user voluntarily reveals that data to the phone company.

Roberts said the realities of modern life make that distinction too simple, especially considering the way many humans and their phones have become essentially inseparable.

"A cell phone—almost a 'feature of human anatomy,' ... tracks nearly exactly the movements of its owner. While individuals regularly leave their vehicles, they compulsively carry cell phones with them all the time," the chief justice wrote. "A cell phone faithfully follows its owner beyond public thoroughfares and into private residences, doctor’s offices, political headquarters, and other potentially revealing locales....Accordingly, when the Government tracks the location of a cell phone it achieves near perfect surveillance, as if it had attached an ankle monitor to the phone’s user."

Roberts said the courts could not look the other way at that intrusion simply because the way phones work requires sharing that information with wireless carriers.

“Given the unique nature of cell phone location records, the fact that the information is held by a third party does not by itself overcome the user’s claim to Fourth Amendment protection,” the chief justice wrote. “Whether the Government employs its own surveillance technology…or leverages the technology of a wireless carrier, we hold that an individual maintains a legitimate expectation of privacy in the record of his physical movements as captured through CSLI (Cell Site Location Information)."

Roberts' majority opinion says police must get a warrant in ordinary investigations, but could access such information without a warrant in an emergency.

"If law enforcement is confronted with an urgent situation, such fact-specific threats will likely justify the warrantless collection of CSLI," the chief justice wrote. "Lower courts, for instance, have approved warrantless searches related to bomb threats, active shootings, and child abductions. Our decision today does not call into doubt warrantless access to CSLI in such circumstances. While police must get a warrant when collecting CSLI to assist in the mine-run criminal investigation, the rule we set forth does not limit their ability to respond to an ongoing emergency."

The decision Friday stemmed from the prosecution of Timothy Carpenter for conspiring in a series of armed robberies around Detroit. Law enforcement helped nab Carpenter by obtaining cell phone data showing him in the vicinity of the crimes.

However, the case involved a relatively imprecise form of cell-phone tracking that reveals which cell-phone tower a phone was connected to and when. The data can also show the rough direction of the phone, but not with the near-pinpoint accuracy of GPS. Collection of that sort of GPS information is also likely to require a warrant in most circumstances under Friday's decision.

Roberts’ ruling builds on two other Supreme Court cases decided in recent years. In 2012, the high court ruled that attaching a GPS tracker to a suspect’s car bumper constituted a search that required a judge-issued warrant.

And in 2014, the Supreme Court recognized for the first time the central role of cell phones in the lives of nearly all Americans, holding that police could not rummage through the entire contents of a phone simply because its owner was arrested.

At arguments in that case, Roberts seemed less than tech-savvy, expressing doubt there would ever be a legitimate reason for a person to have two phones. But the chief justice wound up writing a sweeping majority opinion declaring that phones now contain so much data about a person that they are simply unlike a wallet, purse or any other items that someone would normally have in his or her possession when arrested.

The court's other conservative justices filed three opinions dissenting from the ruling Friday. Justice Anthony Kennedy, joined by Justices Clarence Thomas and Samuel Alito, said the fact that customers voluntarily allow companies to collect location information means they assume the risk of disclosure to the government.

"Here the Government did not search anything over which Carpenter could assert ownership or control. Instead, it issued a court-authorized subpoena to a third party to disclose information it alone owned and controlled. That should suffice to resolve this case," Kennedy wrote.

Kennedy also warned that the court was privileging location data over all kinds of other records that police can routinely obtain under prior precedents.

"According to today’s majority opinion, the Government can acquire a record of every credit card purchase and phone call a person makes over months or years without upsetting a legitimate expectation of privacy. But, in the Court’s view, the Government crosses a constitutional line when it obtains a court’s approval to issue a subpoena for more than six days of cell-site records in order to determine whether a person was within several hundred city blocks of a crime scene," Kennedy wrote. "That distinction is illogical and will frustrate principled application of the Fourth Amendment in many routine yet vital law enforcement operations."

Alito penned a dissent joined by Thomas saying that records obtained through a subpoena shouldn't be considered a search that implicates the Fourth Amendment's protections against unreasonable search and seizure. In Carpenter's case, authorities got the phone records through a subpoena provision in federal law that allows law enforcement to get limited data on phone and email use without satisfying the somewhat greater requirements for a full search warrant.

Gorsuch went his own way in a solo dissent, urging the court to stop considering individuals' "expectation of privacy" and to instead use a framework that focuses more on intrusions on property rights.

"Just because you entrust your data—in some cases, your modern-day papers and effects—to a third party may not mean you lose any Fourth Amendment interest in its contents," the court's newest member said. "I doubt that complete ownership or exclusive control of property is always a necessary condition to the assertion of a Fourth Amendment right."

Gorsuch said he would have ruled against Carpenter because his lawyers never raised the property-based arguments in lower courts.

However, the high court's only Trump appointee said longstanding precedents allowing relatively easy access to landline phone records and bank records are "wrong" and should be overturned.

"Where those cases extinguish Fourth Amendment interests once records are given to a third party, property law may preserve them," Gorsuch declared.