New York University Public Law and Legal Theory Working Papers

Document Type



Chicago Journal of International Law, Vol. 11, No. 1, Winter 2011


Scholarship and advocacy needs to bring defender duties to the forefront of any discussion and investigation of armed conflicts. The necessarily joint contribution of attackers and defenders alike to civilian harm must be recognized. Any investigation of an armed conflict must focus on the duties of both parties and evaluate the feasibility of attacker compliance with some of the more open-ended obligations of international humanitarian law (IHL), such as the so-called duty of proportionality, as a function in part of the extent of defender compliance with its duties.

There are open areas in IHL. States that have acceded to Additional Protocol (AP) I are not necessarily bound by ICRC interpretations and they and states that have declined to ratify AP I can play an active role in formulating and urging others to adopt rules of practice that strike the right balance between attacker and defender duties. Even if, for example, there is widespread international recognition that, at some abstract level, the duty of proportionality is grounded in customary law, the content of that duty is not necessarily identical to the wording contained in AP Article 57. The effectiveness of such a duty, including the ability of military commanders to implement it in the air and on the ground, may well depend on serious consideration, elaboration and implementation of defender duties, for defenders are often in the superior position to minimize civilian exposure to the dangers of military operations.

Defender duties in armed conflicts is a neglected area of IHL. This needs to change if the overall mission of this body of law – minimization of harm to civilians – is to have any reasonable prospect of being realized.

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