A local judge in Arizona ruled Friday that the Tucson Police Department (TPD) does not have to disclose records related to the use of stingrays, also known as cell-site simulators, under the state’s public records act.

According to a Saturday report from Capitol Media Services, a state news wire, complying with reporter Beau Hodai’s public records request "would give criminals a road map for how to defeat the device, which is used not only by Tucson but other local and national police agencies." Hodai sued the TPD and the City of Tucson in March 2014 to force them to hand over such records.

The devices are often used covertly by local and federal law enforcement to locate target cellphones and their respective owners. However, stingrays also sweep up cell data of innocent people nearby who have no idea that such collection is taking place. Stingrays can be used to intercept voice calls and text messages as well.

Both manufacturers and law enforcement have been notoriously tight-lipped about precisely how such devices are acquired and implemented. Former federal magistrate judge Brian Owsley (now a law professor at Indiana Tech) has been unsuccessful in his efforts to unseal orders that authorize their use despite intimate familiarity with the legal system. And just last month, local prosecutors in a Baltimore robbery case even dropped key evidence that stemmed from stingray use rather than allow a detective to fully disclose how the device was used.

The ruling by Judge D. Douglas Metcalf and related court documents are not available on the Arizona court’s website, but Ars will file a request to obtain them when the court re-opens on Monday morning.

Capitol Media Services noted that Tucson provided a filing from Bradley Morrison, chief of the FBI’s Tracking Technology Unit, who argued that even giving up small details of stingray use would be harmful to law enforcement.

"Much like a jigsaw puzzle, each detail may aid in piecing together other bits of information, even when the individual piece is not of importance itself," the wire quoted him as including in his statement.

"In turn, this would provide them the information necessary to develop defense technology, modify their behaviors, and otherwise take countermeasures designed to thwart the use of this technology."

Spying, a world away

On Sunday, Siv Alsen of Norway’s Norwegian Police Security Service (PST) told the Associated Press that one of its sister agencies, the National Security Authority, started an investigation into the use of stingrays in Oslo. The Norwegian newspaper Aftenposten reported last week that stingrays were discovered around the capital city, particularly near the parliament and the prime minister’s residence.

In a Norwegian-language statement (Google Translate) posted to its website, the PST said its "main focus is on whether these findings can be traced to illegal intelligence activities of foreign states."

Neither the Norwegian National Security Authority nor GSMK, the German company that helped the Norwegian reporters, immediately responded to Ars’ request for comment.

"It could be private actors or state actors," Arne Christian Haugstøyl, the head of the PST told The Local. "I can’t on the basis of these discoveries say that it is a foreign intelligence agency, but I can say that we know that foreign intelligence agencies have this kind of capacity. And in our preventive work we advise those looking after Norwegian interests not to talk about sensitive issues on mobile phones.