The Supreme Court just ruled that the Fourth Amendment protects cell-site data gathered by providers. Why is this a big deal? Law enforcement officers will now have to show probable cause and secure a warrant before they can rummage through cell tower records that capture users’ movements.
The case, Carpenter v. United States, arose from a string of retail robberies. After the FBI arrested four men suspected of burgling Radio Shack stores—and a T-Mobile store—in Michigan and Ohio, one flipped and provided information about additional accomplices.
Armed with cell numbers their informant provided, and others from his call record, agents applied for a court order to access the suspects’ cell-site data under the Stored Communications Act. And that’s a low bar: Law enforcement just has to show reasonable grounds to believe the records were relevant to an investigation.
The government used that data to convict Timothy Carpenter of six counts of robbery and five counts of using a firearm during a federal crime of violence. Using 127 days’ worth of cell-site records—almost 13,000 data points—they showed Carpenter was near four of the stores as they were being robbed. Problem is, Carpenter argued on appeal that data shouldn’t have been admissible. He had a reasonable expectation of privacy, and the Fourth Amendment warrant requirement should have applied.
The district court disagreed, as did the Sixth Circuit Court of Appeals, which hears federal appeals from Kentucky, Michigan, Ohio and Tennessee. The Supreme Court, however, sided with Carpenter, five to four. Chief Justice Roberts wrote for the majority, joined by Justices Ruth Bader Ginsburg, Stephen Breyer, Sonia Sotomayor, and Elena Kagan.
The court’s decision hinged on the “third-party doctrine,” a pre-digital rule that information shared willingly is fair game. The government claimed individuals are giving up their tracking data willingly, and the products are business records that aren’t protected under the Fourth Amendment. The broad strokes make sense, Roberts wrote, but the precedent that generated third-party doctrine acknowledged its limitations. The nature of the information and an individual’s expectation of privacy are also relevant.
The majority leaned heavily on the “unique nature” of cellphone records.
Cell phone location information is not truly “shared” as one normally understands the term. In the first place, cell phones and the services they provide are “such a pervasive and insistent part of daily life” that carrying one is indispensable to participation in modern society. Second, 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. ... Apart from disconnecting the phone from the network, there is no way to avoid leaving behind a trail of location data. As a result, in no meaningful sense does the user voluntarily “assume the risk” of turning over a comprehensive dossier of his physical movements.
The precedent is critical. Deciding that cell-site records were “willingly” shared would have opened the door for the court to find leagues of passively collected data—from app usage to data on third-party servers—just as accessible to law enforcement. Now, there’s solid ground to contest unwarranted digital intrusions.
Every justice in the minority filed a dissent. Including, unsurprisingly, Justice Neil Gorsuch. Just as unsurprisingly, his logic misses the mark: As Roberts wryly notes, Gorsuch doesn’t understand why “someone’s location when using a phone is sensitive.” Another indication he may have rubbed the chief justice the wrong way: A snarky footnote. Roberts notes that Gorsuch “faults us for not promulgating a complete code addressing the manifold situations that may be presented by this new technology, under a constitutional provision turning on what is ‘reasonable,’ no less.” That’s high-level legal sniping.
This five-justice majority’s the same one that saved Obamacare, and it’s a grouping we’re likely to see more often should Trump get to replace any of the more liberal justices—or swing-vote Anthony Kennedy. Roberts has proved he has some flexibility, intellectually speaking. Moderation is indeed the right tack for a chief justice concerned with his legacy. Taking the court too far in one direction bodes poorly for the longevity of its decisions.