Court case

[Commentary] When the government engages in prospective cell-site surveillance, it obtains a court order requiring a cell provider to provide the phone’s location at that moment in “real time.” That contrasts with collection of historical cell-site records, when the government obtains a court order requiring the provider to hand over stored records retained by a cell provider in the ordinary course of business from some time in the past. Although every circuit court and state supreme court to rule on historical cell-site collection has concluded it is not a search, the Florida Supreme Court ruled in Tracey v. Florida that prospective cell-site surveillance is a search. Importantly, Tracey went out of its way to say that it was ruling only on prospective surveillance and not on historical collection. On May 22, the U.S. Court of Appeals for the Fifth Circuit ruled in United States v. Wallace that the reasoning of its precedents on historical collection applies equally to prospective cell-site surveillance. In Wallace, the Texas Department of Safety had a warrant out for the arrest of a gang member. The police knew the suspect’s cell phone number, so they obtained what the opinion calls a “Ping Order” authorizing the police to determine the locations of cell site towers being accessed by a number.

[Kerr is the Fred C. Stevenson Research Professor at The George Washington University Law School]