The Fourth Amendment Moves To The Cloud: Chatrie V. United States And The Future Of Digital Privacy

• Published date: 08 July 2026
• Subject Matter: Government, Public Sector, Privacy, Technology, Privacy Protection, Constitutional & Administrative Law, New Technology
• Law Firm: WilmerHale
• Author: Mr Whitney Russell, George P. Varghese, Michael Baer and Samson F. Cohen

WHAT YOU NEED TO KNOW:

• Law enforcement accessing cell-phone location data is a Fourth Amendment search. By a 6–3 vote, the Court held that police intrude on a user's reasonable expectation of records about the user's cell phone location through a geofence warrant, notwithstanding the third-party doctrine.
• Protection does not depend on time limits or the amount of data. The Court refused to grant the government a “grace period” for brief retrievals (here, two hours), holding that a search is a search, regardless of the quantity or sensitivity of what it turns up.
• The Court demurs on probable cause and particularity. Having concluded that accessing Location History data was a search, the Court passed on the questions of whether the geofence warrant met the Fourth Amendment requirements of probable cause and particularity, leaving for another day how narrowly a geofence warrant must be drawn to pass constitutional muster.
• The Court divides over how far the Fourth Amendment reaches beyond location data. Its logic—protecting data a user “reasonably views as his own”—could have broad application, extending to other cloud-stored information. The separate opinions reveal a deepening split over the governing Fourth Amendment framework for digital evidence.

On June 29, 2026, in Chatrie v. United States, the Supreme Court held in a 6–3 decision that police conduct a Fourth Amendment “search” when they obtain a person's cell phone location data through a geofence warrant, notwithstanding the third-party doctrine.¹ Writing for five of the justices in the majority, Justice Elena Kagan concluded that “[a]n individual has a reasonable expectation of privacy in records about his cell phone's location” and that the police “intrude on that constitutionally protected interest when they demand the information—even though for only a limited time, and from a third-party tech company.”²

This Client Alert (1) summarizes the majority opinion and the separate writings, including the division on the Court over how to analyze Fourth Amendment claims; (2) explains why the decision is a direct extension of Carpenter v. United States and Riley v. California; and (3) highlights the forward-looking questions the decision raises—including what other digital information is now likely protected, how categorical that protection is and whether the warrant at issue will ultimately be upheld. For background on geofence warrants and the lower-court decisions that preceded this one, see our prior Client Alert “The Impact and Future of the Fifth Circuit's New Hard-Line Stance on Geofence Warrants.”

The Court's Decision

A geofence warrant is a tool that lets investigators work backward from a crime scene to a suspect. Rather than start with a known suspect, the police draw “a ‘geofence'—a virtual perimeter—around the crime scene” and obtain a warrant compelling a technology company to turn over data about all the cell phones present in that area over a set period of time.³ Because these warrants invert the usual sequence of an investigation, they are often called “reverse warrants.”⁴

The data at issue in Chatrie was Google's “Location History,” which the Court described as “a time-stamped record of every place a cell phone has been.”⁵ When enabled, Location History logs a phone's position “[e]very two minutes or so,” drawing on Wi-Fi, Bluetooth, cell tower sites, GPS, and IP address information to fix the phone's location to within roughly 20 meters and even to estimate which floor of a building the phone is on.⁶ The case arose from the 2019 robbery of a credit union in Midlothian, Virginia. Investigators obtained a geofence warrant directed to Google for a 150-meter radius around the credit union, and through a complex three-step process described in the warrant application, narrowed the universe of users and ultimately identified suspects.

At step one of that process, Google produced “anonymized location data for all cell phones within the geofence in the hour between 4:20 and 5:20 p.m. (30 minutes before to 30 minutes after the robbery).”⁷ At step two, police officers attempted to narrow the list of cell phones by comparing time-stamped location data for each device against “the known time and location information that is specific to this crime.”⁸ Google then provided additional anonymized data: “cell-phone locations both inside and outside the geofence during a two hour period (so now from 3:50 to 5:50 p.m.).”⁹ Finally, at step three, the police further winnowed the list by comparing that information against crime-specific information, and Google “turn[ed] over identifying information for each user on the final list, including his name and phone number.”¹⁰ In “executing steps two and three, law enforcement initially sought unbounded data and account information from all 19 devices identified at step one.”¹¹ “[O]nly because Google insisted” on a narrower request, law enforcement “eventually settled on requesting data from nine devices at step two.”¹² Google ultimately produced identifying information for three users—one of whom was Okello Chatrie, who was later charged with the robbery.¹³

The Court set as a backdrop for its analysis the recurring challenge of “adhering to” settled Fourth Amendment principles “in the face of new technologies,” emphasizing that “no government official should have free access to the most closely kept aspects of [Americans'] lives.”¹⁴

Applying those Fourth Amendment principles to the specific technology at issue, the Court held that obtaining Location History data from Google was a search. To...