Further Reading Appeals court: It doesn’t matter how wanted man was found, even if via stingray sued the City of Chicago and numerous police officials in a proposed federal class-action lawsuit, claiming that he and countless others were unconstitutionally searched when the police used a cell-site simulator without a warrant.

In the suit, Jerry Boyle, who describes himself as an “attorney and longtime volunteer legal observer with the National Lawyers’ Guild,” alleged that while attending the “Reclaim MLK Day” event in Chicago nearly two years ago, his phone was targeted by the Chicago Police Department’s device, better known as a stingray. Boyle argued that his Fourth Amendment and First Amendment rights were violated as a result.

Stingrays are used by law enforcement to determine a mobile phone's location by spoofing a cell tower. In some cases, stingrays can intercept calls and text messages. Once deployed, the devices intercept data from a target phone along with information from other phones within the vicinity. At times, police have falsely claimed the use of a confidential informant when they have actually deployed these particularly sweeping and intrusive surveillance tools. Often, they are used to locate criminal suspects.

The 32-page lawsuit, which was filed in federal court in Chicago on Thursday, specifically notes where and when the stingray was used, on January 15, 2015, “at approximately 8:00pm at the protest, near the 2200 block of West Ogden Avenue.”

However, the civil complaint does not explain exactly how the plaintiff knows this information.

“The evidence regarding CPD's use at that event is something that will be disclosed during the litigation,” Matt Topic, one of Boyle’s lawyers, e-mailed Ars.

The Chicago Police Department did not immediately respond to Ars’ request for comment.

A new hope

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This case, however, marks a rare—perhaps the only—civil case where a person has alleged an unconstitutional search via the use of a stingray.

“I’m not aware of any stingray case in a civil context,” Brian Owsley, a former federal magistrate judge who is now a law professor at the University of North Texas, told Ars. When Owsley was on the federal bench, he famously pushed back against government requests to authorize the use of such devices.

“Typically the posture is that some criminal defendant learns about the use of a stingray related to their criminal proceedings and there’s a challenge based on that,” he continued. “Boyle hasn’t been charged with anything and doesn’t appear likely that he’s going to be charged and still is coming in and asserting that his constitutional rights were violated. That’s really the unique part. That’s the atypical thing at a minimum.”

When is a “search” not a search?

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Still, Matt Topic has had some previous success in lawsuits against the CPD. Topic successfully represented a local journalist who filed a public records request to get the dashcam video depicting the fatal shooting of teenager Laquan McDonald. He has also represented a privacy activist, Freddy Martinez, in his quest to get more public records released on the CPD’s stingray capabilities.

“We contend that it is a search,” Topic told Ars. “The stingray physically trespasses upon the phone to obtain information from it. Whether the phone is in public at the time does not change that, just as it would be an improper search to open up a briefcase being carried around in public. That said, though, stingrays do not distinguish between public spaces and private ones. In many instances, a stingray deployed on a public street will necessarily take information from phones within the private spaces (like homes) in range of the device.”

Just two months ago, the 7th US Circuit Court of Appeals—the controlling appellate court that covers Illinois, Indiana, and Wisconsin—ruled in favor of the government in a related case (United States v. Patrick) that a wanted man who was located via stingray in public indeed had no reasonable expectation of privacy in his location.

In that case, federal prosecutors conceded that use of a stingray was, in fact, a search. But the Chicago Police Department has made no such concession for now.

But in that same case, Circuit Chief Judge Diane Wood lambasted secrecy surrounding the device in a lengthy dissent. “We know very little about the device, thanks mostly to the government’s refusal to divulge any information about it,” she wrote. “Until recently, the government has gone so far as to dismiss cases and withdraw evidence rather than reveal that the technology was used.”

Brett Max Kaufman, an attorney with the American Civil Liberties Union, told Ars that Boyle’s case could be viewed, in some ways, as a continuation of Patrick. “This new suit tees up the clear Fourth Amendment question about stingrays that Patrick didn’t end up addressing,” he e-mailed.