The Supreme Court Tells the Government to Get a Warrant

A highly watched case ends in a 5–4 ruling in which Chief Justice John Roberts and the high court’s liberals inch ever closer to stricter privacy standards.

Jonathan Ernst/Reuters

The Supreme Court can’t dodge ‘em all. So, on Friday, it actually decided Carpenter v. United States, a closely watched case testing how federal law-enforcement agents could legally obtain four months’ worth of cellphone location records as part of an investigation of a rash of bank robberies in Michigan.

The government had not argued that it could simply demand the location records from a cellular service provider; it had argued that a federal statute, the Stored Communications Act, gave it the authority to get the records by showing a federal magistrate that there were “reasonable grounds to believe” that they were “relevant and material to an ongoing criminal investigation.” In response, the Court did not hold that the government couldn’t get cellphone location records; it said it can—providing it gets a search warrant. A warrant requires “probable cause,” a higher standard than that set by the act.

The records involved stored information of which cellphone towers a cellphone user has “pinged” by making calls, sending or receiving texts, checking email, or using the web. Those pings, over a long enough period of time, can produce a comprehensive picture of the owner’s movements, life, work—and, of course, possible crimes. That’s exactly what happened in Carpenter; the government obtained more than four months’ worth of locations, and used that evidence to convict defendant Timothy Carpenter of six counts of bank robbery and six of use of a weapon in violent crime. He was sentenced to serve more than 100 years in prison.

The cellphone data fits awkwardly into existing Fourth Amendment doctrine, because until recently there has been really nothing like it. It is, as Chief Justice John Roberts wrote in his majority opinion, “detailed, encyclopedic, and effortlessly compiled”—a powerful tool for law enforcement.

Here’s an opinion by Justice Samuel Alito arguing that new technology requires new Fourth Amendment doctrines:

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. In this case, for four weeks, law enforcement agents tracked every movement that respondent made in the vehicle he was driving. We need not identify with precision the point at which the tracking of this vehicle became a search, for the line was surely crossed before the 4-week mark.

Alito wrote those words in a 2011 case, United States v. Jones, in which he concurred as the Court held that a GPS tracker attached to a suspect’s car for one month constituted a “search” for which a warrant was required. Friday, however, Alito dissented—arguing that a four-month use of cellphone data was not a search and did not require a warrant. My first reaction (and I suspect that of some others) was, “Who are you and what have you done with Samuel Alito?”

Alito, as we will see, had reasons for his apparent flip; and Carpenter on Friday jumbled the Court’s usual ideological categories. The vote count was 5–4; the opinion was written by Roberts, with the votes of the four moderate liberals—Ruth Bader Ginsburg, Stephen Breyer, Elena Kagan, and Sonia Sotomayor. Justice Anthony Kennedy wrote an angry dissent, as did each of the other three conservatives, Alito and Justices Clarence Thomas and Neil Gorsuch.

The real issue in Carpenter was whether the Court would or should recognize the changed technological universe Americans live in, or would insist on deciding 21st-century issues with 20th-century doctrines. The case jumbled two venerable lines of Fourth Amendment precedent. One, set out in a case called Katz v. United States, asks whether an individual has a “reasonable expectation of privacy” in a given location or activity, whether inside the home or nominally in public. The Katz Court held that there was such an “expectation” in a public phone booth (younger readers see one here). The other line of cases, called the “third-party doctrine,” states that individuals have no “expectation of privacy” in materials—such as bank records or lists of phone numbers they call—that they turn over to businesses instead of keeping themselves.

Obviously the cellphone records (the technical term is “cell-site location information,” or CSLI) are kept by the phone companies; users don’t own them and ordinarily never see them. Their utility to law enforcement is glaringly obvious—phone providers keep them for five years, and police can use them to determine weeks, months, or years of a suspect’s movements.

In 2014, Roberts wrote the majority opinion in Riley v. California, which held that authorities need a warrant to download data on a cellphone even after a lawful arrest of its owner. In that opinion, and in Friday’s, Roberts tried to turn the Court’s attention to the changed world of digital and cellular communications, and its potential to give government an “intimate window into a person’s life, revealing not only his particular movements, but through them his ‘familial, political, professional, religious, and sexual associations.’” For this reason, Roberts argued, the Court should extend the “reasonable expectation” test for the first time to information held by a third party.

Unlike most “third party” materials, he noted, the CSLIs are not “truly ‘shared’ as one normally understands the term. … [A] cell phone logs a cell-site record by dint of its operation, without any affirmative act on the part of the user beyond powering up.” The extension of the “expectation” has implications for future cases involving, say, emails, texts, or other digital information.

Roberts was at pains to claim that the “decision today is a narrow one.” The records obtained in this case—one company turned over 127 days’ worth, the other, which had been used when the suspect was “roaming,” was asked for seven but only had two—were excessive. Shorter-term requests (as, for example, asking for all numbers near a specific robbery site at a specific time) might not require a warrant; neither might national-security cases, nor “exigencies” such as “the need to pursue a fleeing suspect, protect individuals who are threatened with imminent harm, or prevent the imminent destruction of evidence.” But except in such cases, he wrote, “We decline to grant the state unrestricted access to a wireless carrier’s database of physical location information.”

Each of the four conservatives wrote his own dissent; Kennedy (joined by Thomas and Alito) argued that the majority had invented a new doctrine that “puts needed, reasonable, accepted, lawful, and congressionally authorized criminal investigations at serious risk in serious cases.” Carpenter did not own the records the government seized; and, Kennedy noted, Congress, in the Stored Communications Act, had provided a real, if lesser, standard of protection by requiring police to get an order from a magistrate based on “specific and articulable facts” suggesting that the records are “relevant and material” to an investigation. Thomas wrote a classic dissent suggesting that all the caselaw beginning with Katz ought to be scrapped, with courts protecting only individuals’ true property interests. Gorsuch wrote a separate dissent proposing a different property-based set of doctrines of his own invention.

There have always been, on privacy questions, two Alitos—the present-day Alito, who has seldom met a “guilty” verdict or a criminal sentence that he didn’t want to uphold, and the Alito of the Future, who has long worried about the exposure of private information to government and the public through computer and internet technology.

Future Alito had written in Jones, the GPS case; but Carpenter seems to be Days of Future Past, this dissent written by Lock-‘Em-Up Sam. The two cases are not precisely the same: In Jones, the government acted without a warrant and denied that the placement of the tracker was any kind of search at all; in Carpenter, the government relied on a statute in which Congress made a judgment about what level of protection to provide. “If the American people now think that the Act is inadequate or needs updating, they can turn to their elected representatives to adopt more protective provisions,” Alito wrote. He cited the work of Orin Kerr, a top Fourth Amendment expert at the University of Southern California law school and used it to argue that “[i]n circumstances involving dramatic technological change, the best solution to privacy concerns may be legislative. A legislative body is well situated to gauge changing public attitudes, to draw detailed lines, and to balance privacy and public safety in a comprehensive way.”

The best argument I have heard for the government—one that is cited in Kennedy’s dissent—also comes from Kerr. Cellphones make their users easier to track, he says; they also make it easier for the users to commit and conceal crimes, by allowing fast communication among, say, a gang of bank robbers like the ones at issue in Carpenter.

In Jones, the GPS case, the government was arguing for an unlimited right to track anyone without any kind of warrant or order. In Friday’s case, the legislative body had assessed some aspects at least of the new technology. There was a case for leaving that judgment undisturbed; the Court decided otherwise, however, and future cases will now develop the scope of its ruling.