An anonymous reader writes: The Guardian reports that the use of stingray technology — devices that simulate cell towers in order to gather phone data — is not limited to intelligence agencies and law enforcement. It turns out the Internal Revenue Service owns some of the devices as well. It's unknown how or why the tax agency uses the stingray devices. The only reason The Guardian figured it out was that they happened to see an IRS invoice from when they paid a company to upgrade one of their devices and provide training on its use. It's thought they're being used when the IRS collaborates with other agencies to knock down money laundering operations. "... there are currently between 2,000 and 3,000 "special agents" in the IRS who form the criminal investigation division (CID). They have the ability to get PEN register orders – the only authority needed to use Stingray devices."