by Christopher Zoukis

The United States Court of Appeals for the Seventh Circuit has refused to remand a case for further fact-finding about the government's use of cell-site simulators during investigations.

Damian Patrick was wanted for violating parole. In an effort to locate him, Milwaukee police obtained a search warrant which authorized the use of cellphone data. The warrant specifically authorized the collection of data from Patrick's cellphone service provider in order to locate him. Unbeknownst to the magistrate that issued the warrant, the Milwaukee police employed a cell-site simulator, also known as a Stingray, in order to find Patrick.

When Patrick was located, he was in the passenger seat of a car. A gun was in plain view, and he was ultimately charged and convicted of being a felon in possession of a firearm. He appealed the conviction, arguing that his arrest was unlawful. Patrick initially made no argument about the use of a Stingray device, because the government did not reveal its use until after he filed his opening brief.

The appellate court found the arrest to be lawful, because the Milwaukee police "were entitled to arrest him without a warrant of any kind, let alone the two warrants they had." The court reasoned that this was so because the police had probable cause to arrest him for a parole violation, and he had no privacy interest while in a public place.

"A person wanted on probable cause (and an arrest warrant) who is taken into custody in a public place, where he had no legitimate expectation of privacy, cannot complain about how the police learned his location," ruled the court.

The majority opinion did not render any opinion regarding the use of the Stingray, but did quote from a Department of Justice policy guidance memorandum which notes that the device does not capture any data, "only the relative signal strength and general direction of a subject cellular telephone." Based at least in part on the DOJ's benign description of the Stingray, the majority punted any further analysis.

A strongly worded dissent by Seventh Circuit Chief Judge Wood disagreed with this decision. The dissent thought it quite important that the court understand how the police learned of Patrick's location, because the answer to that question could implicate the Constitution. Judge Wood argued that this was doubly true because "[w]e know very little about the [Stingray], thanks mostly to the government's refusal to divulge any information about it." The judge went on to note that the government has gone so far as to dismiss other cases rather than reveal any information about the capabilities and usage of the Stingray.

"Even if the Stingray revealed no information beyond Patrick's location, we must know how it works and how the government used it before we can judge whether it functions in a manner sufficiently different from the location-gathering methods specified in the warrant that it amounted to a search outside the warrant's scope," wrote Judge Woods.

Judge Wood's point is important because it is known that a Stingray can be configured to capture emails, texts, images and other data, and that it can also be used to eavesdrop on telephone conversations. Because the location warrant in question did not allow for electronic surveillance of the cellphone itself, any such usage would be illegal. Judge Wood was clearly suspicious of how the Stingray was used here, and how it might be used in the future.

"It is time for the Stingray to come out of the shadows, so that its use can be subject to the same kind of scrutiny as other mechanisms, such as thermal imaging devices, GPS trackers, pen registers, beepers and the like," wrote the Chief Judge. "[T]he Supreme Court might take a dim view of indiscriminate use of something that can read texts and emails, listen to conversations, and perhaps intercept other application data housed not just on the target's phone, but also on those of countless innocent third parties." See:  United States of America v. Patrick, No. 15-2443 (7^th Cir. 2016).

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