A Technology-Centered Approach to Quantitative Privacy

47 Pages Posted: 15 Aug 2012

See all articles by David C. Gray

David C. Gray

University of Maryland Francis King Carey School of Law

Danielle Keats Citron

University of Virginia School of Law

Date Written: August 14, 2012


We are at the cusp of a historic shift in our conceptions of the Fourth Amendment driven by dramatic advances in technologies that continuously track and aggregate information about our daily activities. The Fourth Amendment tipping point was marked this term by United States v. Jones. There, law enforcement officers used a GPS device attached to Jones’s car to follow his movements for four weeks. Although Jones was resolved on narrow grounds, five justices signed concurring opinions defending a revolutionary proposition: that citizens have Fourth Amendment interests in substantial quantities of information about their public or shared activities, even if they lack a reasonable expectation of privacy in each of the constitutive particulars. This quantitative approach to the Fourth Amendment has since been the focus of considerable debate. Among the most compelling challenges are identifying its Fourth Amendment pedigree, describing a workable test for deciding how much information is enough to trigger Fourth Amendment interests, and explaining the doctrinal consequences. This Article takes up these challenges.

Our analysis and proposal draw upon insights from information privacy law. Although information privacy law and Fourth Amendment jurisprudence share a fundamental interest in protecting privacy interests, these conversations have been treated as theoretically and practically discrete. This Article ends that isolation and the mutual exceptionalism that it implies. As information privacy scholarship suggests, technology can permit government to know us in unprecedented and totalizing ways at great cost to personal development and democratic institutions. We argue that these concerns about panoptic surveillance lie at the heart of the Fourth Amendment as well. We therefore propose a technology-centered approach to measuring and protecting Fourth Amendment interests in quantitative privacy. As opposed to proposals for case-by-case assessments of information “mosaics,” which have so far dominated the debate, we argue that government access to technologies capable of facilitating broad programs of continuous and indiscriminate monitoring should be subject to the same Fourth Amendment limitations applied to physical searches.

Keywords: Fourth Amendment, Privacy Law, United States v. Jones

Suggested Citation

Gray, David C. and Citron, Danielle Keats, A Technology-Centered Approach to Quantitative Privacy (August 14, 2012). Available at SSRN: https://ssrn.com/abstract=2129439 or http://dx.doi.org/10.2139/ssrn.2129439

David C. Gray (Contact Author)

University of Maryland Francis King Carey School of Law ( email )

500 West Baltimore Street
Baltimore, MD 21201-1786
United States

HOME PAGE: http://www.law.umaryland.edu/faculty/profiles/faculty.html?facultynum=598

Danielle Keats Citron

University of Virginia School of Law ( email )

580 Massie Road
Charlottesville, VA 22903
United States

Do you have a job opening that you would like to promote on SSRN?

Paper statistics

Abstract Views
PlumX Metrics