A Stingray is a cellphone tracking device that mimics a cellphone tower. It forces all of the mobile phones around it to connect to it, and then it can obtain the phones’ exact locations and other information. It’s not the sort of device you can pick up at Best Buy; it’s manufactured by a maker of military and space technology, and you can imagine how handy it is if you’re searching for someone. In some cases, a judge can make a request for a service provider to share a phone’s general location, then after driving around that area with a Stingray, it can find the exact location.
In 2014, that’s what police in Maryland did in their search for a shooting suspect. Using the Stingray, they turned up the suspect and the gun inside a nearby home. The problem is that when the judge issued the order for the phone company to provide some general information on the suspect’s phone, he didn’t know that police planned to use a Stingray to identify his exact location. The suspect’s lawyers argued that using a Stingray amounted to doing a search, which, by law, requires a search warrant. The Maryland Special Court of Appeals agreed, deciding that the gun and anything else found in the search was inadmissible in court.
What’s the implication? The Stingray is pretty widely used. In Baltimore alone, police used the Stingray in some 2,000 cases in 2016, mostly without warrants. The ACLU says that at least 61 police departments in 23 states and the District of Columbia own Stingrays. Several states already have laws requiring warrants before police can use the Stingray, and the federal government also requires warrants for using the Stingray in its investigations.
Police departments outside those jurisdictions may see the tide turning and seek warrants before using the Stingray. Otherwise, they may risk losing convictions due to inadmissible evidence. But this case, and others like it, may push the question closer to the Supreme Court, where privacy officials hope that it may be decided for good.