This is the first part of a two-part series. The second part looks at how it could Big Tech companies like Google, and not the courts, that have the last word on regulating geofence warrants.

In the span of two months, the Fourth and Fifth Circuits have issued diametrically opposed opinions on the constitutionality of geofence warrants—a type of reverse-search warrant that seeks to access a company’s location data to find a specific device in a specific period.