A “geofence” is like a border. The term has digital roots – if you drag a series of lines around a map so they enclose an area, you have “geofenced” that area.
A “geofence warrant” is when law enforcement defines such an area and then asks tech companies for all digital evidence that occurred in that area during a specific range of time.
For example, if a burglary took place at 10:00 p.m., the police department could ask Google for the names of every Android device in an three-block radius from 9:00 to 11:00. Instead of being person-centric and asking, “Was this person there?,” a geofence warrant is geography-centric and asks, “Who was there?”
Why I Looked It Up
I was reading an article where Google stated that geofence warrants have become fully 25% of the law enforcement requests it responds to. Requests for this type of information is increasing at a dramatically faster pace than any other type of request.