A group of 15 shifting suspects committed a string of armed robberies at Radio Shack and T-Mobile stores. When four of the men were arrested, one soon implicated Carpenter and Sanders as the ringleaders. The man who confessed gave investigators his cell phone and the phone numbers of his partners in crime.
Investigators tracked down owner information for these numbers, as well as other numbers from the confessing robber’s phone. Ultimately, seven of the robbers implicated Carpenter as the organizer and gun supplier for most of the robberies. The robbers also stated that Carpenter and Sanders had served as lookouts during the robberies.
Investigators obtained an order under the Stored Communications Act (18 USC § 2703(d)) for historical cell site location information (CSLI) for Carpenter’s and Sanders’ phones as well as 14 other phones of co-conspirators. The CSLI showed that Carpenter and Sanders used their cell phones within a half-mile of the crimes.
Carpenter and Sanders protested the use of the CSLI, arguing that they had an expectation of privacy and drawing a comparison to continuous GPS tracking disfavored by recent decisions of federal courts, including the U.S. Supreme Court in United States v. Jones (132 S.Ct. 945 (2012)). The court made quick work of a general claim to privacy in CSLI, holding that cell phone communication “content … is protected under the Fourth Amendment, but routing information is not.” Moreover, cell phone users must know that the phone location is being tracked by a provider: “Any cellphone user who has seen her phone’s signal strength fluctuate must know that, when she places or receives a call, her phone ‘exposes’ its location to the nearest cell tower and thus to the company that operates the tower.”
The court also dismissed the analogy to GPS surveillance. First, placing a GPS tracking device involves a physical trespass on the vehicle, person or item. Second, the GPS tracker reveals much more precise detail about location. The GPS tracker is generally accurate within approximately 50 feet and is even able to point to the tracker’s location within a building. As the court noted, the CSLI was obtained from a third-party provider, not a tracking device. It “could do no better than locate the defendants’ cellphones within a 120- (or sometimes 60-) degree radial wedge extending between one-half mile and two miles in length.”
The court held that the CSLI was properly admitted. Carpenter also complained about the 116-year sentence imposed by the trial court and Sanders protested his much-shorter 14-year sentence, but both sentences were upheld.