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.