Geofence Warrants a Big No-No

 This is a big deal, as the Electronic Frontiers Foundation says.  It's also going to SCOTUS, as the Fifth Circuit and Fourth Circuit disagree on a major element.

Following a post-office robbery, the police obtained a "geofence warrant" for a large area.  Google coughed up two individuals who were arrested.

...[The Fifth Circuit] determined that under the Supreme Court’s landmark ruling in Carpenter v. United States, individuals have a reasonable expectation of privacy in the location data implicated by geofence warrants. As a result, the court broke from the Fourth Circuit’s deeply flawed decision last month in United States v. Chatrie, noting that although geofence warrants can be more “limited temporally” than the data sought in Carpenter, geofence location data is still highly invasive because it can expose sensitive information about a person’s associations and allow police to “follow” them into private spaces....

There's the ticket to SCOTUS.

Also:

...geofence warrants require a provider, almost always Google, to search “the entirety” of its reserve of location data “while law enforcement officials have no idea who they are looking for, or whether the search will even turn up a result.” Therefore, “the quintessential problem with these warrants is that they never include a specific user to be identified, only a temporal and geographic location where any given user may turn up post-search. That is constitutionally insufficient.”...

Yes, but only if you think the Fourth Amendment is valid.  There's very good reason to think that the FBI and NSA disagree and will continue to do whatever the Hell they want to do.