Enlarge / Dozens of apps on your phone know where you are, whether you're home, at a doctor's appointment, at the airport, or sitting still in a blank white room to pose artfully for a photo shoot. (credit: JGI | Tom Grill | Getty Images )

An increasing number of law enforcement agencies, including the US Secret Service, are simply buying their way into data that would ordinarily require a warrant, a new report has found, and at least one US senator wants to put a stop to it.

The Secret Service paid about $2 million in 2017-2018 to a firm called Babel Street to use its service Locate X, according to a document ( PDF ) Vice Motherboard obtained . The contract outlines what kind of content, training, and customer support Babel Street is required to provide to the Secret Service.

Locate X provides location data harvested and collated from a wide variety of other apps, tech site Protocol reported earlier this year. Users can "draw a digital fence around an address or area, pinpoint mobile devices that were within that area, and see where else those devices have traveled" in the past several months, Protocol explained.