SURVEILLANCEIn 2021, the Police Took a Page Out of the NSA’s Playbook: 2021 in Review
Dragnet searches were once thought to be just the province of the NSA, but they are now easier than ever for domestic law enforcement to conduct as well. With increasing frequency, law enforcement has been using unconstitutional, suspicionless digital dragnet searches in an attempt to identify unknown suspects in criminal cases.
With increasing frequency, law enforcement has been using unconstitutional, suspicionless digital dragnet searches in an attempt to identify unknown suspects in criminal cases. Whether these searches are for everyone who was near a building where a crime occurred or who searched for a keyword like “bomb” or who shares genetic data with a crime scene DNA sample, 2021 saw more and more of these searches—and more attempts to push back and rein in unconstitutional law enforcement behavior.
While dragnet searches were once thought to be just the province of the NSA, they are now easier than ever for domestic law enforcement to conduct as well. This is because of the massive amounts of digital information we share—knowingly or not—with companies and third parties. This data, including information on where we’ve been, what we’ve searched for, and even our genetic makeup, is stored in vast databases of consumer-generated information, and law enforcement has ready access to it—frequently without any legal process. All of this consumer data allows police to, essentially, pluck a suspect out of thin air.
EFF has been challenging unconstitutional dragnet searches for years, and we’re now seeing greater awareness and pushback from other organizations, judges, legislators, and even some companies. This post will summarize developments in 2021 on one type of dragnet suspicionless search—reverse location data searches.
Reverse Location Searches: Geofence Warrants & Location Data Brokers
Reverse location searches allow the police to identify every device in a given geographic area during a specific period of time in the past as well as to track people’s paths of travel. Geographic areas can include city blocks full of people unconnected to the crime, including those living in private residences and driving on busy streets.
Unlike ordinary searches for electronic records, which identify a suspect, account, or device in advance of the search, reverse location searches essentially work backward by scooping up the location data from every device in hopes of finding one that might be linked to the crime. The searches therefore allow the government to examine the data from potentially hundreds or thousands of individuals wholly unconnected to any criminal activity and give law enforcement unlimited discretion to try to pinpoint suspect devices—discretion that can be deployed arbitrarily and invidiously.
Two main types of reverse location searches gained prominence in 2021: Geofence warrants and searches of location data generated by device applications and aggregated and sold by data brokers.
