In a new amicus brief on a case involving data surveillance and emerging technologies, the Policing Project at NYU School of Law has urged the Court to reject an all-or-nothing ruling and to instead rule in a way that encourages lawmakers to act

FOR IMMEDIATE RELEASE
March 9, 2025

Media Contact: Joshua Manson, Policing Project at NYU School of Law, joshua.manson@nyu.edu, (914) 357-0000

New York, NY – This morning, the Policing Project at NYU School of Law filed an amicus brief in Chatrie v. United States urging the Court to avoid ruling in the all-or-nothing fashion advocated by the parties, and instead encourage urgently needed legislation to establish meaningful guardrails on data surveillance.

In Chatrie, the Court will consider the constitutionality of “geofence” warrants, which allow police to search cell phone users’ location data to identify suspects. The Court is considering the questions of whether the use of geofence warrants constitutes a “search” under the Fourth Amendment, and if so, whether they are permissible.

The organization’s brief argues that geofence warrants are a search under the Fourth Amendment, but that the Court should avoid either allowing or prohibiting all geofence warrants. Doing so, the brief argues, would in effect provide carte blanche for police to access the massive amounts of data available through new technologies or categorically remove a powerful public safety tool.

Instead, the brief argues that the Court should address this and other novel data surveillance questions raised by emerging technologies by ruling in a way that encourages lawmakers to act. Advanced surveillance technologies raise significant and highly complex privacy risks that are better addressed through nuanced legislation that can address the many issues raised by data surveillance, including privacy, data retention, minimization, and data security.

The brief specifies what that legislation can and should include, including distinctions among kinds of data that may be collected and alleged crimes for which data surveillance is allowed; limits on data storage and retention; and accountability and oversight. With comprehensive laws in place, the Court would then be well positioned to evaluate which frameworks provide the required constitutional protections.

“In this country, we are long overdue for comprehensive protections against indiscriminate and unaccountable mass data surveillance by law enforcement,” said Policing Project founder and faculty director Barry Friedman, who also authored a 2026 University of Pennsylvania Law Review article on the topic titled “The Constitutionality of Data Surveillance. “However, given the technical complexities of these tools, the risks they present to our liberties, and their potential public safety benefits when used responsibly by police, the right fix for this is legislative. Lawmakers can and should develop thoughtful, carefully tailored protections that protect both individual liberties and public safety, and the Court shouldn’t get in their way.”

Read the full brief here: https://www.policingproject.org/s/Chatrie-amicus-brief.pdf.