The U.S. Supreme Court on Monday heard arguments in a landmark legal case that could redefine digital privacy rights for people across the United States.
The case, Chatrie v. United States, centers on the government’s controversial use of so-called “geofence” search warrants. Law enforcement and federal agents use these warrants to compel tech companies, like Google, to turn over information about which of its billions of users were in a certain place and time based on their phone’s location.
By casting a wide net over a tech company’s stores of users’ location data, investigators can reverse-engineer who was at the scene of a crime, effectively allowing police to identify criminal suspects akin to finding a needle in a digital haystack.
But civil liberties advocates have long argued that geofence warrants are inherently overbroad and unconstitutional as they return information about people who are nearby yet have no connection to an alleged incident. In several cases over recent years, geofence warrants have ensnared innocent people who were coincidentally nearby and whose personal information was demanded anyway, been incorrectly filed to collect data far outside of their intended scope, and used to identify individuals who attended protests or other legal assembly.
The use of geofence warrants has seen a surge in popularity among law enforcement circles over the last decade, with a New York Times investigation finding the practice first used by federal agents in 2016. Each year since 2018, federal agencies and police departments around the U.S. have filed thousands of geofence warrants, representing a significant proportion of legal demands received by tech companies like Google, which store vast banks of location data collected from user searches, maps, and Android devices.
Chatrie is the first major Fourth Amendment case that the U.S. top court has considered this decade. The decision could decide whether geofence warrants are legal. Much of the case rests on whether people in the U.S. have a “reasonable expectation” of privacy over information collected by tech giants, like location data.
It’s not yet clear how the nine justices of the Supreme Court will vote — a decision is expected later this year — or whether the court would outright orde …