Hours before a scheduled meeting to surrender records to the American Civil Liberties Union about the use of controversial "stingray" cellphone tracking devices, Sarasota, Florida, police canceled the meeting, saying the U.S. Marshals had seized the records and they were no longer in police possession. Calling the move "blatant violations of open government laws," in the words of staff attorney Nathan Freed Wessler, the ACLU promptly sued, protesting the handoff of sensitive documents to the feds and seeking their return.

Also known as "IMSIcatchers," stingray devices simulate cellphone towers and trick cellphones into connecting, revealing their location. They are frequently used by federal and local officials under old-fashioned "trap and trace" warrants which conceal the intrusive nature of the modern technology.

Law enforcement officials are often cagey about the technology, both in terms of its capabilities, and also the loose legal standards under which it is used. Old-fashioned warrant applications appropriate to the physical wiretapping era often conceals the actual nature of the surveillance even from judges. In 2011, FBI agents were ordered to be more forthcoming in warrant applications when using stingray devices.

So, how could a federal agency seize surveillance records local officials are required to maintain? According to the ACLU "a few hours before that appointment, an assistant city attorney sent an email cancelling the meeting on the basis that the U.S. Marshals Service was claiming the records as their own and instructing the local cops not to release them. Their explanation: the Marshals Service had deputized the local officer, and therefore the records were actually the property of the federal government."

The feds then physically removed the records to an unknown location.

ACLU officials soon found that the records were also no longer in the possession of the county court which had authorized use of the technology, nor are there any docket entries acknowledging their existence, even though the law requires that such information be kept.

The feds apparently made a clean sweep of the information sought by the civil liberties group.

The ACLU lawsuit, if successful, would prevent the Sarasota Police Department from turning over any more records to the U.S. Marshals, and force it to recover the original records for public disclosure.

Separately, a Florida judge agreed with the ACLU that Tallahassee police should surrender information regarding the use of stingray devices. In that case, the technology was allegedly used to track a phone to a suspect's apartment in the absence of a warrant.