From Shaun Waterman, at the Washington Post:
FBI investigators for at least five years have routinely used a sophisticated cellphone tracking tool that can pinpoint callers’ locations and listen to their conversations — all without getting a warrant for it, a federal court was told this week.
The use of the “Stingray,” as the tool is called, “is a very common practice” by federal investigators, Justice Department attorneys told the U.S. District Court for Arizona Thursday, according to the American Civil Liberties Union.
Installed in an unmarked van, Stingray mimics a cellphone tower, so it can pinpoint the precise location of any mobile device in range and intercept conversations and data, said Linda Lye, staff attorney at the ACLU of Northern California in a blog post about the case.
The FBI looks like a criminal organization, not a law enforcement organization. They're okay with spying on anyone and everyone for any reason at all. They don't believe that they're constrained by judges or the law.