(Kiyoshi Ota/Bloomberg)

A judge has ruled that Tucson, Ariz., doesn’t have to release records about how it tracks cellphones, which the city argues would aid criminals.

Beau Hodai, a freelance reporter, requested records from the Tucson Police Department in 2013 about the Stingray and Stingray II, cell phone tracking equipment, according to court documents. The equipment acts like a cell tower, and can measure signal strength to determine the location of a phone.

Hodai requested all records created using the equipment, any e-mails about it, and any records about its purchase and maintenance.

The department responded to Hodai’s request with some documents that were partially redacted. Hodai said in the complaint he learned Tucson redacted portions of the documents at the request of Harris Corporation, which produces the Stingray and Stingray II.

Hodai filed a lawsuit in March, saying Tucson violated the law for not releasing the information, but Pima County Superior Court judge Douglas Metcalf ruled on Thursday against him, writing Tucson “is under no obligation to do so because it is not a proper request for records.”

“Not all records maintained by public officers are subject to public inspection,” Metcalf wrote in the ruling. “When the public officer shows that access to the public records ‘might lead to substantial and irreparable private or public harm’ … then the records are not subject to public inspection.”

Tucson argued releasing records would “compromise sensitive law enforcement techniques” and could enable criminals to “piece together” how the technology was used.

Daniel Pochoda, senior council at the ACLU of Arizona, said the group disagrees with the ruling.

“It was just a very badly reasoned decision,” he said in an interview with the Washington Post. The equipment picks up not just the cellphone targeted by officers, but all in the vicinity, Pochoda said, and according to the ruling, Tucson said search warrants for the equipment’s use did not exist.