Document Type


Publication Date

Winter 2-6-2011


The use of GPS surveillance technology for prolonged automated surveillance of American citizens is proliferating, and a direct split between the Ninth and D.C. Circuits on whether warrants are required under the Fourth Amendment for such use of GPS technology is bringing the issue to a head in the Supreme Court. A Petition for Certiorari is pending in the Ninth Circuit case which held that warrants are not required, and a second Petition is likely from the Government in the D.C. Circuit case holding that warrants are required. In this paper, we argue first, that where a technology enables invasion of interests at the heart of the Fourth Amendment’s concern -- protection of citizens from arbitrary government intrusions into their private lives -- the Court’s precedents require warrants to prevent abuse, and second, that the type and scope of information collected by prolonged automated GPS surveillance enables governments to monitor a person’s political associations, their medical conditions and their amorous interests, in a way that invades their privacy and chills expression of other fundamental rights.

Our argument differs significantly from previous scholarship by tracing a continuous emphasis in Fourth Amendment jurisprudence on review of the potential for abuse of surveillance methods. Moreover, we are the first to argue that in protecting against abuse the Court has drawn a firm line between technology that simply enhances the natural senses of law enforcement officials, and technology that creates novel, non-biological “senses.”

In Part I of this paper, we trace the origins of the Fourth Amendment’s protections against law enforcement abuse, present evidence that GPS surveillance technology is in fact being abused, and discuss the impact unfettered abuse of the technology will have on the individual rights of citizens. In Part II, we explain the Court’s historic approach to new surveillance technologies, noting that the Court has carefully examined new technologies to prevent any end-runs around legal doctrine from eroding personal privacy, and showing that the Court has always required warrants where technology goes beyond enhancement of senses to the creation of new non-biological “senses.” In Part III, we explain why the Supreme Court’s ruling on the use of beeper technology to enhance visual surveillance in United States v. Knotts, 460 U.S. 276 (1983), does not apply to the use of GPS technology as a replacement for visual surveillance. Finally, in Part IV, we explain how prolonged automated GPS surveillance invades a reasonable expectation of privacy and chills the exercise of core constitutional rights.