Lawfare Daily: Chatting on Chatrie with Adam Unikowsky, Michael Dreeben, and Richard Salgado

This episode of Lawfare Daily examines the Supreme Court case *Chattree v. United States*, which centers on the constitutionality of geofence warrants—search warrants that compel tech companies like Google to identify all devices within a virtual perimeter around a crime scene. The case arises from a bank robbery investigation where law enforcement used a geofence warrant to access anonymized location data from 19 devices, narrowed it down to nine suspects, and ultimately de-anonymized three, one of whom was convicted. The core legal question is whether this process constitutes a Fourth Amendment search and whether the warrant is sufficiently particularized. Legal experts Adam Unikowsky, Michael Dreeben, and Richard Salgado dissect the case, debating whether the government’s use of algorithms to scan millions of user accounts amounts to a search, the applicability of *Carpenter v. United States*, and the broader implications for digital privacy. They also discuss the practical realities of how companies like Google handle such warrants, the limitations of analogies to physical searches, and the risks of expanding government surveillance powers under the guise of technological necessity. The conversation underscores the tension between law enforcement’s need to solve crimes and the erosion of privacy in the digital age. The episode highlights the evolving nature of Fourth Amendment doctrine in response to technological change. While the government argues that geofence warrants are narrow and supported by probable cause, the petitioners contend they are functionally general warrants that violate the Fourth Amendment’s core principle of particularity. Experts debate whether the digital world’s infrastructure—such as cloud-based accounts—should be treated as a protected space akin to a physical home or locker. Richard Salgado emphasizes that the real-world experience of users is not captured by outdated analogies, while Michael Dreeben warns that a broad ruling could undermine future surveillance reforms. The stakes are high: a decision either upholding geofence warrants could enable mass data sweeps, while striking them down could hinder investigations. Ultimately, the episode reveals a pivotal moment in digital privacy law, where the court may be forced to redefine what constitutes a search in an era of algorithmic surveillance.