Geofence warrants, a type of reverse search warrant, compel companies, like Google, to turn over substantial information about devices interacting with their technology within a particular geographic region. For this reason, geofence warrants mark an unprecedented increase in the government's ability to locate individuals without investigation. This primer will show you how geofence warrants are constructed and outline strategies to challenge these warrants when they appear in criminal cases. 

 To identify suspects, law enforcement officers are turning increasingly to reverse search warrants, such as geofence warrants and keyword search warrants. These are searches used to find suspects and are not conducted to find evidence on a targeted individual. This trend presents novel challenges to the Fourth Amendment and privacy rights in the United States. 

In People v. Seymour, 21CR20001, defense challenges the constitutionality of a reverse keyword warrant served on Google for anyone who searched for a particular physical address over 15 days, and moves to suppress all resulting evidence. The Fourth Amendment Center’s Litigation Director, Michael Price, is co-counsel for the defense. 

Subject matter experts and litigators from NACDL’s Fourth Amendment Center explain and discuss some of the important digital technology issues that defense counsel will very likely encounter in these cases. The faculty focus on reverse searches, facial recognition, and device searches.

Reply brief of the appellant in US v. Chatrie. Michael Price, the Fourth Amendment Center's Litigation Director, is co-counsel for Mr. Chatrie. 

As a criminal defense organization, we do not profess to possess expertise in policing practices insofar as those practices do not directly intersect with the criminal justice system. But many police practices do have a direct impact on the treatment of accused persons, the degree to which their cases are litigated justly, and case outcomes. Accordingly, we offer a few key insights, which we hope will find their way into the Commission’s recommendations.

(Updated Jan. 18, 2023, see below) Since 2010, law enforcement agencies in the United States have had direct access to an increasing volume of bulk data about people’s wire transfer transactions. The core of this previously secret program is a database containing records of virtually every money transfer of more than $500 sent to, from, or within Arizona, California, New Mexico, Texas, or Mexico.

This practice advisory aims to: 1) explain what was involved in this bulk money transfer surveillance program; and 2) provide defense counsel with potential challenges to it.

20^th Annual State Criminal Justice Network Conference
August 18-20, 2021 | Held Virtually

Police departments across the country are increasing using predictive algorithms to decide where to patrol and who to investigate. These tools are also being used to create databases that label people as threats and feed them into the criminal legal system.

NACDL's Fourth Amendment Advocacy Committee carefully and comprehensively studied issues concerning the current United States Postal Service Mail Covers regime following the revelations in The New York Times investigative report in connection with the 2014 U.S. Postal Service audit of the program. The concerns raised by this program and its operation fall squarely within NACDL's long history of advocating for the vitality of Americans' privacy and Fourth Amendment rights -- in the courts, in the legislatures, in executive agencies, and in the public arena. [Released April 2015]

How Data-Driven Policing Technologies Entrench Historic Racism and 'Tech-Wash' Bias in the Criminal Legal System

This NACDL Predicative Policing Task Force Report (1) calls attention to the rapid development and deployment of data-driven policing; (2) situates data-driven policing within the racialized historical context of policing and the criminal legal system; (3) makes actionable recommendations that respond to the reality, enormity, and impact of data-driven policing; and (4) suggests strategies for defense lawyers in places where data-driven policing technology is employed.

Over the past several years, the government has increasingly turned to hacking and malware as an investigative technique. The Federal Bureau of Investigation has begun deploying software designed to infiltrate and control, disable, or surveil a computer's use and activity. The ACLU created a guide, to which NACDL and EFF contributed, that sets out key legal arguments and strategies for challenging evidence seized by government-installed computer malware. [Released March 2017]

In this webinar, we address the ethical implications of government surveillance and client communications. Defense lawyers regularly use phone calls, texts and emails to communicate with clients, investigators, witnesses and others associated with their cases. Many of these communications are privileged, yet government surveillance programs can capture and store them. We explore how this happens, and how defense lawyers can keep their communications out of government hands.

In this webinar, we address the ethical implications of government surveillance and client communications. Defense lawyers regularly use phone calls, texts and emails to communicate with clients, investigators, witnesses and others associated with their cases. Many of these communications are privileged, yet government surveillance programs can capture and store them. We explore how this happens, and how defense lawyers can keep their communications out of government hands.

Presented by: Colin Fieman Assistant Federal Public Defender, Tacoma, WA; and Paul Ohm, Professor of Law, Georgetown University Law Center

This webinar was supported in part by Grant No. 2013-MU-BX-K014 awarded by the Bureau of Justice Assistance.