PHOENIX -- Arizonans are not entitled to details of exactly how police departments can track cell phones -- and their owners -- a judge has concluded.
In a new ruling, Pima County Superior Court Judge Douglas Metcalf said it would not be in the "best interests of the state' for the public to be able to view training manuals and other materials from the Tucson Police Department on how the agency uses a device called the "StingRay" and the more recent "StingRay II."
He said the documents being sought would pretty much give criminals a road map of how to defeat the device which is used not only by Tucson but other local and national police agencies.
City Attorney Michael Rankin called the ruling "reasoned."
But attorney Daniel Pochoda of the American Civil Liberties Union of Arizona who represents a freelance reporter seeking the documents said he disagrees with Metcalf's ruling and how the judge arrived at his decision. Pochoda said, though, no decision has yet been made on whether to appeal.
But the legal fight already has produced some information.
In its response to the lawsuit, the city admitted it has used the device at least five times. And Lt. Kevin Hall has acknowledged the agency has not sought or obtained a warrant in any of those cases.
The device itself and its basic operation is not entirely a secret.
It relies on the fact that cell phones essentially log in with each tower they are near. That is necessary so that incoming calls are routed to the correct tower and that ongoing calls are handed off from tower to tower as someone travels through an area.
The StingRay, made by Harris Corp., mimics a cell tower. So every phone within range logs in.
Police then can comb through that data to find the cell phone they are seeking. And the device is portable, meaning officers can actually take it door to door to pinpoint the phone for which they are searching.
Beau Hodai, a reporter, wanted more details.
Some of that related to specifics of each use. The city did produce records of four of the cases where it used the device; Metcalf said Hodai was not entitled to anything on the fifth as it related to a still-active investigation.
But he also requested the "quick reference sheets" which are instructions on how to use the equipment. And he wanted the department's training materials including a equipment worksheet and a computer presentation that explains how the equipment works.
Metcalf said Arizona's Public Records Law has a presumption in favor of disclosure. But he said that can be overcome if the public agency provides a legitimate reason to keep documents secret.
At that point, Metcalf said, it is up to a court to weigh whose interests win out. And in this case, the judge said that the city's arguments, including national security interests, trump the claims by the ACLU that the public needs to know if its privacy is being invaded.
Lawyers for Tucson relied on a sworn statement from Bradley Morrison, an agent with the FBI who is the chief of the agency's Tracking Technology Unit. Morrison argued that disclosure of even minor details of the device would be harmful.
"Much like a jigsaw puzzle, each detail may aid in piecing together other bits of information even with the individual piece is not of importance itself," the agent said in his statement -- and the judge repeated in his ruling. That includes information that "adversaries," including criminals and foreign powers, could use on the capabilities and limitations of the equipment.
"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," Morrison wrote.
At least one of those "countermeasures," though, already is public: Documents produced in a Florida case show that while cell phones can be tracked even if they are not being used, the technology is useless if the phone is turned off entirely.
Metcalf also said there is legal precedent -- though none from Arizona was cited -- to withhold from the public "sensitive law enforcement investigative techniques."
The judge said that presumption against disclosure cannot be overcome simply because someone wants to know how law enforcement uses technology to investigate crimes.
Metcalf did acknowledge that Hodai and the ACLU do have some "legitimate and important public purposes" in seeking disclosure, including whether public privacy is compromised by use of the device. But the judge said the records the city provided to him, which he reviewed in his chambers, do not answer that question.
"Rather, the records show how to use the equipment," he said, meaning they are not subject to public release.
Metcalf also denied a specific request for any records concerning the department's Counter Narcotics Alliance Unit as well as any records that mention the FBI.
The judge said the number of records sought does not make them exempt from disclosure. But Metcalf said a request needs to be for a specific record or set of records rather than simply a demand for any document that may include a specific word or term.
"In order to examine the record, the person must identify it," the judge wrote.
Follow Howard Fischer on Twitter at @azcapmedia.