The Baltimore Police Department has been accused of violating federal law with its use of stingray cell phone trackers. In a complaint filed with the Federal Communications Commission (FCC) on Tuesday, August 16th, three civil rights groups said the police department hasn't obtained the license required to use stingray technology, adding that it violates the Communications Act by "willfully interfering" with cellular networks. As Ars Technica Reports, the 38-page complaint also argues that the use of stingray trackers disproportionately affects African-American communities.