The US Supreme Court on Monday restricted law enforcement’s use of “geofence” search warrants, ruling 6-3 in Washington that citizens have a constitutional right to privacy regarding their mobile phone location history.
In the 6-3 ruling, the highest court in the United States declared that individuals hold a reasonable expectation of privacy concerning the location data compiled by their devices and the applications running on them. Consequently, law enforcement agencies must secure a formal search warrant before demanding historical geofence data from technology firms like Google.
Why Geofence Warrants Require a Search Warrant
The justices argued that because mobile users do not actively or intentionally share their location history with tech platforms simply by using their services, the traditional “third-party doctrine” does not apply here. This legal doctrine historically allowed authorities to bypass warrants for data voluntarily handed over to third parties, such as telecommunication providers.
What Are Geofence Warrants and Why Are They Controversial?
Geofence warrants are powerful digital dragnets. They allow police forces to compel tech companies to search database records and identify every single user present within a specific geographic boundary at a given time. In practice, investigators draw a virtual boundary on a map and ask a judge to order companies like Google to scour their vast location archives for matching devices.
Civil liberties advocates have long criticised these “reverse” search warrants as unconstitutional, arguing they are excessively broad and sweep up the sensitive personal data of completely innocent bystanders.
While the Supreme Court agreed with these privacy concerns, it stopped short of issuing an outright ban on geofence warrants. Instead, the ruling permits police officers to submit narrower, highly targeted data requests provided they secure a warrant first.
The Fourth Amendment Shield
Under this ruling, the US Fourth Amendment—which safeguards citizens against unreasonable searches and seizures—now explicitly covers mobile location data. Police are not barred from accessing historical location records; they must simply demonstrate probable cause to a judge that a suspect has committed a crime before obtaining the warrant.
The Legal Battle: Chatrie v. United States
The landmark ruling stems from the case of Chatrie v. United States. Okello Chatrie challenged his bank robbery conviction, arguing that the evidence used against him was gathered via an unconstitutional geofence warrant. His legal defence team contended that such warrants allow investigators to “search first and develop suspicions later”, bypassing long-standing constitutional norms.
Traditionally, investigators must establish probable cause linking a specific individual to a crime before searching. Critics argue geofence warrants turn this fundamental principle on its head.
The Supreme Court intervened after conflicting rulings on geofence warrants in lower appeals courts across the United States created legal uncertainty.
Impact on Past Convictions
The immediate impact of this ruling on previous convictions remains uncertain. A Department of Justice spokesperson did not immediately respond to requests for comment.
Chatrie’s original sentence is unlikely to change, as lower courts previously determined that police acted in “good faith” when they gathered the geofence evidence under the laws of the time. Chatrie’s attorneys did not respond to requests for comment.
The Supreme Court has now instructed the Court of Appeals to review whether the specific warrant used in Chatrie’s case demonstrated sufficient probable cause to be deemed valid.
How Tech Giants Are Responding to Privacy Pressures
In response to a relentless surge in police data requests, some tech giants have already altered how they handle user data. Google, for instance, has transitioned to storing location histories directly on users’ physical devices rather than on company servers, effectively preventing the company from complying with geofence demands. However, other major firms that store location records, including Microsoft, Uber, and Yahoo, continue to receive these warrants regularly.