[Photo credit: U.S. Department of Defense, Flickr]

In recent years, the range and number of state actors undertaking extraterritorial lethal-force operations have drawn attention to — and often criticism of — the various international and domestic legal authorities referenced by those actors. The question of where and how the legal framework governing counterterrorism intersects in extraterritorial lethal-force operations with the jus ad bellum, IHL, human rights law, the law of state responsibility, and international criminal law has arisen in connection, for example, to the use of specific weapons platforms, such as unmanned combat aerial vehicles (or drones), and to attacks targeting leaders of particular groups, such as al-Qaeda. Unlike with the jus ad bellum, IHL, and human rights law framings, however, the counterterrorism framing does not appear to require the same level of political consensus to legitimize these operations. These questions have grown more complex as the Security Council has increasingly referenced multiple, purportedly simultaneously applicable, bodies of law, such as in relation to Libya, Mali, Somalia, and Syria.

This research theme will examine the legal and policy dimensions of contemporary extraterritorial uses of lethal force in situations not rising to the level of armed conflict, as well as other types of relevant acts that states undertake to give effect to their policy objectives, such as kidnapping, eavesdropping on foreign citizens, and preventative action that is short of war but that is functionally preemptive. These areas of inquiry will include relevant developments in technology, surveillance, and intelligence issues. The role of the jus ad bellum and human rights in purportedly regulating these practices will be considered, alongside other international and domestic legal frameworks.

Research questions pertaining to the research theme of contemporary extraterritorial uses of lethal force may include:

  • What are the international legal standards pertaining to the extraterritorial use of lethal force, as well as to other coercive actions short of war, such as kidnapping, eavesdropping, and extrajudicial detention?
  • How are long-standing conceptions under the jus ad bellum and, separately, under the jus in bello of “proportionality” and “necessity” being implicated in these operations?
  • To what extent, and in what ways, do the jus ad bellum and international human rights law interface with other legal frameworks in regulating such actions?    

These and related questions have important implications for protection in situations at the cusp of armed conflict, which appear to be increasing in number and ferocity.

Related Projects

Research Assistants


Related Writings from PILAC Scholars

Professor Gabriella Blum

Laws, Outlaws, and Terrorists: Lessons from the War on Terrorism (with Philip Heymann) (MIT Press, 2010) 

Law and Policy of Targeted Killing” (with Philip Heymann), 1 Harvard National Security Journal 145-170 (2010)

Naz Modirzadeh

Folk International Law: 9/11 Lawyering and the Transformation of the Law of Armed Conflict to Human Rights Policy and Human Rights Law to War Governance,” Harvard National Security Journal, Vol. 5, No. 1, pp. 225–304 (2014)

PILAC Affiliate Michael N. Schmitt

Drone Law: A Reply to UN Special Rapporteur Emmerson, 55 Virginia Journal of International Law Digest 13-28 (2014)

With Andru E. WallThe International Law of Unconventional Statecraft5 Harvard National Security Journal 349-376 (2014)

Narrowing the International Law Divide: The Drone Debate Matures, 39 Yale Journal of International Law Online 1-14(2014)

Charting the Legal Geography of Non-International Armed Conflict, 90 International Law Studies 1-19 (2014); 53 The Military Law and Law of War Review __ (2014)

Extraterritorial Lethal Targeting: Deconstructing the Logic of International Law, 52 Columbia Journal of Transnational Law 77 (2013)

Unmanned Combat Aircraft Systems (Armed Drones) and International Humanitarian Law:  Simplifying the Oft Benighted Debate30 Boston University International Law Journal 595-619 (2012)

Drone Operations under the Jus ad Bellum and Jus in Bello:  Clearing the “Fog of Law”, 13 Yearbook of International Humanitarian Law 311-326 (2011)

International Law and Counterterrorism (with Dean Dwigans), in Toward a Grand Strategy Against Terrorism 86-102 (Christopher Harmon et al., eds., McGraw-Hill, 2010)

The Law of War at the Vanishing Point: Reflections on Law and War in the 21st Century, Harvard International Review 64-68 (Spring 2009)

Responding to Transnational Terrorism under the Jus ad Bellum: A Normative Framework56 Naval Law Review 1-42 (2008); International Law and Armed Conflict: Exploring the Faultlines 157-195 (Michael N. Schmitt & Jelena Pejic eds, Leiden, Martinus Nijhoff, 2007)