Kansas Court Rejects Government’s ‘Reverse Warrant,’ Sets Ground Rules For Future Requests

We haven’t seen a lot of legal challenges to so-called “reverse warrants.” This is likely due to their relative novelty. It’s probably also due to the fact that no one “targeted” by these warrants knows about them until well after an investigation has been closed.

Reverse warrants don’t target people or places. They target (and I’m using that term loosely) areas roughly defined/confined by GPS coordinates. Everything inside the geofence is a target. Working backward from the data obtained from companies like Google, investigators try to determine which of these data points is their suspect.

For the time being, it’s mostly up to the judges reading the warrant affidavits to raise challenges to the methods used or the broadness of request. And, so far, we’ve only seen one rejection of a reverse warrant, albeit one rejected twice by consecutive judges (a magistrate and a district court judge).

Now we have one more rejection to examine, coming to us via FourthAmendment.com. A magistrate judge in Kansas has rejected [PDF] the government’s attempt to obtain location data from Google. The magistrate notes that judges all over the nation should expect to see more of these as time goes on and should be aware of the constitutional issues at play when the government works backwards from bulk data to identify a criminal suspect. Because this investigative technique is only expected to become more common, this judge has decided to set some ground rules for the government’s future attempts to work its way backwards to probable cause.

The court issues this written order not only to address the subject application, but also to provide guidance for future search warrant applications involving geofence technology given the relatively sparse authority on this issue.

And the court is doing this because this warrant just doesn’t cut it, constitutionally speaking.

Here, the application and accompanying affidavit are not sufficiently specific or narrowly tailored to establish probable cause or particularity. The court therefore denies the application without prejudice.

The order doesn’t detail the federal crime suspected of being committed but does note it involves a heavily trafficked business. The government is seeking location data on every device in the area during a one-hour period. That isn’t narrow enough for the court…