The Privacy Principle

Can international law regulate global surveillance programs without sacrificing national security interests? In the face of unprecedented global terrorist activity, this question takes a near existential form: intercepting a chat room exchange between accomplices in Syria and California can be the difference between timely arrest and mass atrocity. Despite the practical importance of this question, scholarly engagement with it so far has been incomplete. Part of the literature submits that global intelligence programs operate beyond the grasp of legal constraint, thus dooming us to a bleak Orwellian future. The remainder proposes human rights-based solutions, which, on account of the United States, France, Russia, and China having rejected them, remain crippled by difficult issues of state consent and state practice under treaty or customary international law. This Article proposes that this gap can be closed by theorizing the existence of a general principle of law, the Privacy Principle. The Article establishes the Privacy Principle by means of a comparative analysis of the private laws of core states with significant signals intelligence capabilities: the United States, France, Russia, China, Israel, and Iran. This analysis reveals that (1) there is general agreement on the existence of a right to privacy prohibiting physical or virtual surveillance of people when in private; (2) "privacy" can be theorized in terms of reasonable expectations of seclusion as defined by the twin factors of the physical or virtual space affected, and the intimacy of the information at issue; and (3) the "right to privacy" invariably weighs such reasonable expectations of seclusion against the public interest, permitting intrusions when they are proportionate to all relevant interests at stake. This Article demonstrates that the Privacy Principle is part of general international law. It explains how approaching privacy from the perspective of a general principle can achieve the normative goals of the current human rights literature while accounting for the legal and policy objections of its critics. Finally, it shows how the application of the Privacy Principle to global surveillance programs is responsive to today's national security needs: the Privacy Principle prohibits the dragnet collection of data from private persons. Nevertheless, it supports the design of efficient signals intelligence programs capable of detecting threats by monitoring traffic on terrorist propaganda and recruitment websites, and subsequently tailoring deeper surveillance after a threat assessment of this traffic.