Police are using a secret gadget that can track your phone, and they can't talk about it

Law enforcement around the country are using a secretive device known as the StingRay to monitor phone activity in order to track criminals - but they're not allowed to say anything about the technology or how it works, as The New York Times reports.

The technology is capable of capturing texts, emails, phone calls, and location data, the Times details in its report. What's troubling, however, is that the report says the StingRay often obtains information about devices nearby the target rather than just the intended device.

The device caused controversy in Silicon Valley recently when Santa Clara County Sheriff Laurie Smith asked county officials to pay $502,000 for the technology, although she refused to offer details beyond saying it could be used to track the cell phones of terrorists and other criminals, according to the Times.

Although we don't know too much about the StingRay, which sometimes goes by other names such as KingFish, reports have managed to piece together some information about how it's being used and where.

Based on reports, here's what we know:

• It's able to gain such access to mobile devices because it tricks phones into think it's a cell tower, and is often referred to as a "cell site simulator." The Washington Post has a helpful graphic that breaks down how the device works. When the StingRay is turned on, the signals from nearby phones are re-directed to it as if it were a cell tower.
• It's designed to that cell phone carriers and users can't detect its use, according to The Washington Post.
• We don't know exactly how widely the technology has been adopted since police departments are forced to sign nondisclosure agreements overseen by the FBI when purchasing them, reports the Times. But the American Civil Liberties Union has put together a graphic showing all of the states across the country that are believed to be using the StingRay based on available documents and reports. Both state and local police are believed to be using the StingRay in New York, Florida, Texas, Wisconsin, Minnesota, and Illinois, according to the ACLU's map. Only local police are believed to be using the technology in Virginia, North Carolina, Georgia, Missouri, Michigan, Arizona, California, Idaho, Washington and Alaska. StingRay activity in most states is unknown.
• The devices are usually paid for by individual agencies, according to the Times, but in some instances the federal government pays for the cell site simulators through Homeland security grants.
• Although we're hearing a lot about StingRay now, it's not necessarily new. Law enforcement in North Carolina have been said to have used in back in 2013, according to The Washington Post.
• Harris, the company that makes StingRay devices, has made $40 million from spy technology contracts with city, state, and federal authorities in the US, according to procurement records obtained by Ars Technica in 2013.
• There's been a lot of speculation as to how the information obtained by these StingRay devices is being used. "It might be a totally legitimate business interest, or maybe they're trying to keep people from realizing there are bigger privacy problems," Orin S. Kerr, a privacy law expert at George Washington University, told the Times. "What's the secret that they're trying to hide?"