Guest Post: On ‘Humanitarian Intervention’, ‘Lawmaking’ Moments and What the ‘Law Ought to Be’–Counseling Caution Against a New ‘Affirmative Defense to Art. 2 (4)’ After Syria

Guest Post: On ‘Humanitarian Intervention’, ‘Lawmaking’ Moments and What the ‘Law Ought to Be’–Counseling Caution Against a New ‘Affirmative Defense to Art. 2 (4)’ After Syria

[Carsten Stahn is Professor of International Criminal Law and Global Justice at Leiden University and Programme Director of the Grotius Centre for International Legal Studies. He is Co-Editor-in-Chief of the Leiden Journal of International Law, Executive Editor of the Criminal Law Forum and project leader of the Jus Post Bellum Project.]

Harold Koh’s thought-provoking post on Just Security on ‘Syria and the Law of Humanitarian Intervention – Part II’ illustrates the struggles of international law to cope with injustices and violations of legal norms, including the ban of the prohibition of chemical weapons.  Koh argues in favor of a new ‘affirmative defense to Article 2 (4)’ of the United Nations Charter which would allow the ‘lawful threat of limited military intervention’ to counter ‘a deliberate large-scale chemical weapons attack’. He regards Syria as a ‘lawmaking moment’ that should be used to clarify ‘the contours of an emerging exception to a rigid rule’. This argument is based on a number of claims and assumptions that merit reconsideration.

One may easily concur that the law on the use of force contains ‘grey zones’ and that Syria is a ‘hard case’. It is also helpful to set out arguments in ‘legal language that international lawyers’ can debate. But like others (e.g. Kevin Heller and David Kaye), I would argue that is highly questionable whether Syria should be a ‘moment to reframe international law’ in the direction suggested. It may rather be illustrative of the claim of a few to reshape the law in a way that might be seen as a window for abuse by others.

It is deplorable that the Council has been blocked over two years, due to an irresponsible use of prerogatives that are out of time. This has created a ‘vacuum of protection’.  But the fundamental question is whether the solution suggested, i.e. greater flexibility towards military strikes under an ‘affirmative defense to Art. 2 (4)’ is the right remedy to deal with this dilemma. This is a very rudimentary logic. It appears to suggest that unilateral military action is the proper remedy to overcome impasses and inaction by the Council. His argument contains a number of problems that require reconsideration: (i) the framing of the choice, (ii) the use of the label of ‘humanitarian intervention’, (iii) the nature of the proposed ‘defense’ for the use of armed force, and (iv) the approach towards ‘lawmaking’.

1. Framing the underlying choice

The first problem with Koh’s argument that is that it is phrased in a binary ‘either’/’or’ logic. Koh suggests that there is a choice between ‘turning a blind eye (and a deaf ear) to violations’ and the use of military force.  Koh presents intervention as a lesser of two evils. This is a constructed choice. Hardly anyone would seriously suggest that doing nothing is an option in the face of a violation, such as the 21 August 2013 attack on civilians. The question is not so much whether to respond, but rather how to react. The solution suggested by Koh, i.e. remedying a violation through use of force, blurs fundamental categories of law.

The primary norm breached in the Syrian context is a fundamental norm of international law that is prohibited under different bodies of law, including international humanitarian law and international criminal law.  Koh’s logic suggests that use of the force should be an ultima ratio option to respond to such types of violations. This assumption merits questioning. In his case for deviation from the ‘illegality’ rule, Koh mixes different rationales that require different response schemes.  His argument builds a case for military action based on a merger of different objectives: i.e. ‘remedying a humanitarian situation’, preventing ‘the likelihood of future atrocities’, achieving accountability for ‘crimes’, sanctioning the use of chemical weapons, preserving of peace and security. These objectives are all valid and important. But is questionable whether they can be achieved best through a broadening of the options for military force.

International law offers alternative paths to the use of force to achieve rationales, such as accountability, deterrence or sanctioning of jus in bello violations, i.e. preventive diplomacy, lawful countermeasures, international criminal justice, sanctions etc. Broadening the categories of the use of forces has trade-offs. It weakens these options and their underlying regimes (e.g. non-coercive and non-violent response measures under Chapters VI and VIII of the Charter, mechanisms under R2P etc.). It carries the risk of remedying wrongs through means that are ill-equipped to meet the very goals of intervention. In light of these risks, many nations (e.g., G77) have remained reluctant to accept the doctrine of ‘humanitarian ‘intervention’.

Introducing a new ‘affirmative defense’ for military strikes based on Syria crisis would be an open floodgate for other claims. Acceptance of this argument might serve as an incentive for further action outside collective security in other cases involving a threat to international peace and security. For instance, why would other nations be prevented from claiming a similar justification to use force in response to specific incidents or ‘acts of international terrorism’ that have been branded as a threat to international peace and security as such under Resolution 1373 (2001)? Such an approach is vulnerable to abuse and might have detrimental side-effects. It might make the Security Council even more reluctant in the future to engage with threats to international peace and security. A better way forward might be to work towards a more responsible use of veto powers in the future (i.e. understandings on the non-use of the veto in specific situations), rather than declaring the Council irrelevant, as done at the height of the Syria crisis.

2. The label of ‘humanitarian intervention’

The second problem with Koh’s argument is that it uses the label of ‘humanitarian intervention’ to justify the claim for the legality of the threat or use of force. Arguments supporting ‘humanitarian intervention’ reach indeed far back in history. But the weakness of Koh’s reasoning is that assumes that Syria falls squarely under that doctrine and that it may be treated in one historical line with incidents such as Kosovo, Srebrenica etc. This is questionable. This analogy hinges. There are fundamental differences.

In the Syrian case, intervention was not directly aimed at ending atrocities and armed conflict as such, but guided by other purposes: (i) shifting the military balance between the Assad regime and opposition forces and (ii) sanctioning an unlawful means of combat, i.e. use of chemical weapons. This reasoning differs from the necessity arguments and moral dilemmas that underpinned the Kosovo intervention. There are two key differences. The case for intervention sought to remedy and deter a specific modality of action by one party to the conflict. Moreover, the proposed reaction was limited in scope. It was essentially framed as a response to an incident in a crisis, i.e. the use of chemical weapons, rather than as a response situation as such.  This incident represents only a small fraction of the violence committed in the Syrian conflict. This makes it difficult to make a direct historical comparison.  Syria is thus to some extent a ‘new’ type of intervention.

One have doubts whether the doctrine of ‘humanitarian intervention’ offers a proper fit. It is guided by the rationale of protection of victims of conflict. As I have tried to argue in a post on EJIL Talk (and a paper to be published in the Journal of International Criminal Justice), the discourse on military intervention in Syria essentially turned this logic on its head. It used ‘protection’ as a means to achieve accountability through military force. This approach is a step away from historical precedents. It not necessarily desirable in policy terms. It may effectively weaken the impetus and credibility of humanitarian law and erode the virtues of the separation of jus ad bellum and jus in bello.

3. ‘Justification’, ‘mitigation’ or none of them?

A third problem of Koh’s argument relates to the construction of the proposed ‘affirmative defense’. Koh presents the concept as a justification for military action, i.e. as an element excluding the wrongfulness of the respective intervention. As noted by others (e.g., former UK Legal Advisor Bethlehem), such an exception does not form part of the existing concept of countermeasures, as reflected in the 2011 Draft Articles on State Responsibility of the International Law Commission. It is difficult to justify it by analogy to the concept of necessity (Article 25 of the ILC Draft Articles). The ILC made this clear in its corresponding commentary where it noted:

‘The question whether measures of forcible humanitarian intervention, not sanctioned pursuant to Chapters VII or VIII of the Charter of the United Nations, maybe lawful under modern international law is not covered by article 25’.

The consolidation of a new ‘affirmative defense’ would require support and authority that failed to get sufficient consensus in the process leading up to the adoption of the R2P principle by the 2005 World Summit. It shifts the focus back to the logic of a ‘right to intervene’ which remains contested. The key problem with this assertion is that the recognition of the lawfulness of intervention would entail a corresponding duty of the territorial State and others to accept intervention. The proposed claim fails to specify what exactly would have to be accepted and tolerated by ‘others’ under the label of ‘protection of civilians’. Given the lack of specificity of criteria, the different nature of cases of intervention and the divergent reactions thereto, and a lack of clarity on constraining factors, it is hard to find a solid basis in existing customary law.

It is also difficult to construe an affirmative defense’ on practice, such as ex post facto endorsement by the Security Council. This argument was inter alia used in the cases of ECOWAS/ECOMOG action in Liberia or the Kosovo intervention, i.e. Resolution 1244 (1999). But such reactions are neither systematic, nor necessarily based on legal reasoning. Interpreting silence as acquiescence or ex post approval may overstretch the meaning of the underlying resolutions. It makes selective use of Council authority. It suggests that the voice of the Council may be ignored in decisions to initiate strikes, but then become relevant in validation ex post facto. What authority is then left – and why should it be respected by others?

A variation of this claim has been suggested by the late Thomas Franck in his work on Recourse to Force (pp. 180 et seq). He suggested to rely on arguments of ‘mitigation’ to deal with dilemmas of intervention in the absence of authorization. The ‘mitigation’ argument is based on a slightly different approach than the ‘justification’ idea. It recognizes the illegality of intervention. It claims that the intervener should be absorbed from consequences (i.e. ‘excused’ in terms of the language of criminal law), in light of the dilemmas posed by the choice of action. It therefore maintains the illegality rule, but proposes a differentiated treatment as to the consequences of intervention. This logic might be somewhat closer to existing status quo of the law in terms of its  approach.  But it remains questionable whether it should be applied to the mix of justifications for strikes used in the Syrian context.

4.  From ‘law-breaking’ to ‘lawmaking’

A final problem of Koh’s argument is his approach towards ‘lawmaking’. Syria may indeed provide a momentum for further ‘lawmaking’. But the fundamental question is whether such initiatives should focus on the framework relating to the use of force, rather than other frameworks.

Resolution 2118 (2013) marks a step in the right direction. It is disappointing on some aspects (on ‘peace versus justice’, see my earlier post on EJIL Talk), but reassuring on others. It bears striking resemblance with some other thematic resolutions of the Security Council, such as Resolution 1368 (2001). This type of ‘legislative’ activity of the Council  has been criticized by some voices, in light of factors such as (i) the lack of inclusiveness and transparency of Council procedures, (ii) the imprecise nature of certain notions and obligations and (iii) potential conflict with the integrity of treaty regimes. But with these caveats, it offers new prospects to strengthen weaknesses in the existing enforcement regime. Further thematic work of the Council on the ban of chemical weapons could be used to strengthen (i) instruments of prevention, fact-finding and verification, (ii) cooperation with OPCW, (iii) duties of compliance or (iv) response schemes under the R2P doctrine.

An immediate focus on the use of force may stifle this momentum and detract from some of the positive spin-offs that the Syria crisis has produced. Bringing non-military options back to the forefront might turn Syria from a potentially ‘law-breaking moment’ into a ‘lawmaking’ moment.

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Thomas Welch

While it is easy to nitpic with Koh from Europe, he is at least trying to deal with political realities here in the U.S., China and Russia and achieve some progress.  UNSC reform is the more obvious alternative, but has been blocked by France too.   Why not pick on them instead?


An important contribution to the debate.  One of the troubling statements in Harold’s essay involves Article 2(4) of the Charter.  He focuses on the “other” types of force that are proscribed under the third type of force that is covered by the text and rightly offers an analysis why a given use of force may not, on balance, be thwarting of the major purposes of the Charter (esp. re: human rights at stake).  However, he then states that such force would nevertheless be “against” the territorial “integrity” of Syria — which triggers one of the three forms of prohibition.  It was not necessary to make such a conclusion (others here easily criticized his position), especially in the special circumstances of an ongoing civil war and significant recognition of the SNC as the legitimate representative of the Syrian people.  What is the Assad regime under the circumstances?  What entity represents the Syrian people and their quest for self-determination?  The SNC can consent to outside assistance and use of force as a “belligerent” and as the legitimate representative of the Syrian people.  At least, the matter is far more complex than most of the EJIL and Opinio Juris essays seem to recognize.  A strong case can be made… Read more »


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