The report said the devices raise concerns for privacy advocates because law enforcement officials won’t say how often they use them, how the data is used or kept, or whether they get a warrant from a judge before using the technology.
Law enforcement officials declined interview requests and redacted references to the Stingray in public records requested by the Gannett Wisconsin Media Investigative Team. But documents show that the devices have been used for years by both the Wisconsin Department of Justice and the Milwaukee Police Department.
The DOJ device has been in use since at least 2006 and is loaned to federal, state and local agencies for use throughout Wisconsin and neighboring states, according to the report.
The Wisconsin Supreme Court is considering whether a warrant to use a Stingray in a Milwaukee murder case was valid.
“We have very powerful technology that has very important consequences for our privacy, but we don’t have the kind of transparency necessary to kind of understand what the contours of the issue are,” said Byron Lichstein, a defense attorney arguing case. “Even if the targeted information is narrow, the amount and private nature of the information that can be collected is pretty striking.”
A suitcase-sized Stingray masquerades as a cell tower to trick cellphones into connecting to it. It can show phones within a mile or more, depending on the terrain. Records show the DOJ’s Stingray cost more than $150,000 and that the DOJ and Milwaukee police both purchased upgrade packages that topped $100,000.
Specifics on the Stingray are hard to come by since the manufacturer, Florida-based Harris Corp., won’t discuss its technology and requires customers to sign nondisclosure agreements. The devices are not known to intercept the content of calls or text messages, the report said. But they capture location details and, possibly, the numbers with which a given phone is communicating, according to court records and published reports.
“It’s hard to know how all the information is going to be used once it’s collected, so that’s why you need limits on what can and can’t be collected,” said Lichstein, a professor at the University of Wisconsin Law School.
The Wisconsin Legislature passed a bill in February requiring warrants in order to use cellphone tracking technology in most cases.
The legislation, which has yet to be signed by Gov. Scott Walker, would place fewer limits on cellphone tracking than state law requires for traditional search warrants.
Police in other states often use the devices without warrants, including more than 200 times in Florida since 2010, according to court testimony.