This week, USA Today's investigative team shined a light on the Baltimore police department and their use of stingrays. The paper found cops deployed the cell phone trackers in crimes as minor as harassing phone calls, and the authorities would often conceal the results of that surveillance from suspects and lawyers despite the fact that Maryland law "generally requires that electronic surveillance be disclosed in court," according to the paper.

Evidently, the story found the right eyeballs. USA Today now reports that defense lawyers in Baltimore have pledged to examine nearly 2,000 cases involving police using stingrays. The lawyers plan to use their findings to approach judges and for “a large number” of criminal convictions to be overturned, the paper writes.

“This is a crisis, and to me it needs to be addressed very quickly,” Baltimore’s deputy public defender, Natalie Finegar, told USA Today. “No stone is going to be left unturned at this point.”

In general, stingrays, IMSI catchers, or cell-site simulators can be used to determine location by spoofing a cell tower, but they can also intercept calls and text messages. Once deployed, the devices snatch data from a target phone as well as information from other phones within the vicinity. For years, federal and local law enforcement nationwide have tried to keep their existence a secret while simultaneously upgrading their capabilities. But over the last year as the devices have become scrutinized, more information about the authorities' little surveillance secret has been revealed.

Beyond Baltimore, at times cops have gone as far as to falsely claim the existence of a confidential informant while in fact deploying this particularly sweeping and invasive surveillance tool. As such scenarios continued to become public, the Department of Justice announced in May 2015 that it would be reviewing its stingray policies, just four months after claiming that it did not need a warrant to use the device in public. (Private residences are considered different, as that is a location where a person has a "reasonable expectation of privacy.")

According to a surveillance log published earlier by USA Today, there were more than 1,900 cases in Baltimore where police indicated stingray use, and these cases included at least 200 instances where public defender clients were convicted. Finegar told USA Today that she wasn't sure how many criminal cases would ultimately be reopened, but she expects to challenge large number in the end.