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Estreicher on Defender’s Duties in Armed Conflict

NYU Law Professor Samuel Estreicher has posted an interesting working paper on SSRN, titled Privileging Asymmetric Warfare?: Defender Duties Under International Law.  Here is the abstract:

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.

Professor Estreicher essentially argues that the laws of war include certain flexible terms, such as proportionality, “effective warning,” and the obligation of attackers to “do everything feasible” to verify the non-civilian nature of a target.  What is “feasible,” Estreicher argues, may be affected by the fact that a defender is engaging in perfidy or using human shields.  This framework will contribute to the development of a regime that commanders feel they can actually follow, thus generating more compliance with the laws of war, resulting in a higher level of protection for civilians.

The paper’s conclusions are interesting, not least because they offer an interesting platform for political discourse about the laws of war, but I carry some reservations.  If we begin to tell commanders that they may consider an adversary’s violations of IHL in their proportionality calculations, are we in effect re-opening the door to belligerent reprisals against civilian populations (a practice foreclosed by API art. 51)?  My concern is that this framework will lead to an overly contractual interpretation of the laws of armed conflict, leading in fact to greater casualties among populations that (often unwillingly) play host to guerrilla forces.

My reactions, however, are quite tentative, and Estreicher’s work is a novel and useful contribution to this debate.  Thanks to International Law Reporter for the link.

I realize this blog has become rather IHL-heavy in the past weeks.  It’s a consequence of the recent headlines, of my particular interests, and of my refusal to use this space to criticize the officiating at Friday’s U.S.-Slovenia match.  Please accept my assurances that other posts are in the works, and do send any ideas to me (

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