EFF Files Amicus Briefs in Two Important Geofence Search Warrant Cases

The warrants in both the Meza and Chatrie cases encompassed large geographic areas and time periods. In Meza, the police asked for all devices in six discrete, heavily populated areas of Los Angeles during time periods where people were likely to be in sensitive places, like their homes at church or a medical center, or driving along one of the many busy streets included within the geofenced areas. In total, police requested data for a geographic area equivalent to about 24 football fields or five to six city blocks during five morning commute hours. Similarly, in Chatrie, the geographic area was about 17.5 acres (about 3 and a half times the footprint of a New York city block) and included a church, a chain restaurant, a hotel, several apartments and residences, a senior living facility, a self-storage business, and two busy streets.

In our briefs, we argue these warrants are unconstitutional “general warrants” because they don’t require police to show probable cause to believe any one device was somehow linked to the crime under investigation. Instead, they target everyone in the area and then provide police with unlimited discretion to determine who to investigate further. In Meza, we also argue the practice violates CalECPA, California’s landmark electronic communications privacy law.

Chatrie and Meza are the first cases challenging geofence warrants to make it to the appellate level. However, they appear to just be the tip of the iceberg. The number of police requests for geofence warrants has increased dramatically since their first reported use in 2016. According to Google, geofence requests now constitute more than a quarter of the total number of all warrants it receives, and 20% of those come just from law enforcement agencies in California.

There is real reason to be concerned about these overbroad searches. They have, in the past, caused innocent people to be suspected of crimes they didn’t commit. And geofence warrants can and have been used in ways that impact fundamental rights, including free speech and freedom of association. For example, during the protests following the police shooting of Jacob Blake, the ATF used at least 12 geofence warrants to collect people’s location data during protests in Kenosha, Wisconsin, one of which encompassed a third of a major public park for a two-hour window. Police also used a geofence warrant in Minneapolis around the time of the protests following the police killing of George Floyd. And geofence warrants may be used in the near future to target people for reproductive health choices and outcomes. Google has been sufficiently concerned about this possibility to pledge to delete location information shortly after someone visits an abortion clinic, though critics have argued this would be insufficient to protect people.

The Chatrie and Meza cases will both likely be argued sometime later this year. The majority of courts to address geofence warrants in publicly available opinions have raised constitutional concerns, refusing to issue the warrant or suppressing the evidence. We hope these two appellate courts will do the same.

[1] EFF was represented on the Chatrie brief by the NYU Technology Law & Policy Clinic, and the excellent brief was drafted by law students Talya Nevins and Yanan Wang.

Jennifer Lynch is Surveillance Litigation Director at EFF.This article is published courtesy of the Electronic Frontier Foundation (EFF)