Changes in the way that Google handles data related to its Maps and location apps could mean that law enforcement will no longer be able to obtain location data from Google through so-called geofence warrants, according to a Bloomberg article.

Traditional search warrants involve an application to a neutral magistrate requesting to search a person, place, container or records for evidence of a crime.  Issuance of such a search warrant requires a showing that probable cause exists to believe that evidence of criminal activity will be found, meaning that there is evidence to tie the person, place, container or records to the suspected crime.

A geofence warrant does not offer any particularized suspicion of many or any of the persons whose location data is being obtained. A geofence warrant basically asks for the location data of any device that was within a specified geographic area during a designated time range. The location is where the crime occurred and the time range is when the crime is believed to have occurred. Because geolocation data is not exact, such a warrant can scoop up the data of people who had no connection to the crime. In fact, there is no guarantee that the person law enforcement are trying to find (the suspect) will show up in the report generated by Google.  If the suspect did not have an electronic device or did not have location tracking active, then the suspect will not show up in the report.  But to the extent that law enforcement is looking for a single suspect, the report will provide private information about people who law enforcement have no justification to obtain information about.

Currently, Google location data is stored on the company's servers.  This means a geofence warrants is an effort to obtain information from a container consisting of Google servers. A database search can be performed by Google with the specified date, time and location parameters.

Google is making plans to encrypt users' Google Maps location history and store it on the users' devices. Since the data will no longer be stored on the company's servers, there will be no data set on Google servers for the company to search to respond to these warrants. It will also mean that Google will not have access to that data stored on its users' devices. 

While we wait for this pro-privacy measure to be taken, it makes sense to look at the privacy settings on your devices and what access to location data you allow your various apps to have. The location data can be from Google Maps but also from other apps that request your location in order to improve service.

This will still leave cell tower operators as a target for this type of dragnet warrant.