Regulating Resort to Force: A Response and Thanks to Corten

Matthew Waxman is Professor of Law at Columbia Law School, New York.

In the latest issue of EJIL, I write about doctrinal form and jus ad bellum in ‘Regulating Resort to Force: Form and Substance of the UN Charter Regime’, 24 EJIL (2013) 151. Much of the legal debate in this area – among states, scholars, and other international actors – takes place on a substantive axis, focusing on the scope of force prohibitions and exceptions: are they too broad or narrow; too permissive or restrictive?  In this article, I argue that these debates also sometimes explicitly or implicitly include preferences regarding doctrinal form, by which I mean modes of argumentation and analysis through which facts are assessed in relation to legal directives.

Adherents to one orientation, whom I term ‘Bright-Liners’, generally favour governing states’ legal authority to use force unilaterallyby clear and rigid rules that admit little case by case discretion. Adherents to another orientation, whom I term ‘Balancers’, generally believe that the legality of unilateral resort to force should be judged by objective but flexible standards that call for weighing contextual factors, thereby vesting in states some discretion to account for competing values.

 The main point of my paper is that substantive preferences – narrow versus broad international legal authority to use force – often go hand in hand with doctrinal form preferences (i.e. those favouring restrictive authority to use force generally prefer bright-line rules), but that they need not.  By prising apart the substantive debate from the debate about doctrinal form, and analyzing some of the reasons why one form might be better than another, I expose some conflicting but often-buried assumptions about how international law works or fails in this area, and I aim to open up some underappreciated ways to think about legal reform.

I was pleased to learn that EJIL had asked Professor Olivier Corten to comment on my paper (see 24 EJIL (2013) 191), because he has written thoughtful work on interpretive method in this area (see his 2005 article in EJIL on The Controversies Over the Customary Prohibition on the Use of Force) that overlaps with my interests here. In his commentary accompanying my article, subtitled as a response from a Bright-Liner, Corten critiques my paper in three ways.

 I won’t spend much time discussing his first critique because I already acknowledge and address it in the article itself.  He notes that there is not always such a sharp distinction between bright-line rules and flexible standards, and even bright-line prohibitions and exceptions with respect to the use of force contain some “grey zones.”  That is exactly right, a point I make in Part II(A): that my characterizations of competing orientations are really “segments along a spectrum of possible views, rather than two discrete and dichotomous points,” and that what appear at first to be bright-line rules often admit some contextual balancing.  Corten calls it naïve to think otherwise, but in my research I did not often find other Bright-Liners so willing to acknowledge this – after proclaiming the critical importance of regulating any use of force by sharp lines that admit very little balancing.  Nor are other Bright-Liners very clear about how those residual grey zones don’t undermine their arguments in favor of bright-line rules.

Corten’s second and third critiques illustrate some of my main points about debates in this area.  He spends the middle part of his response discussing my characterization of controversies about anticipatory self-defense and self-defense against non-state actors – two contexts in which I believe international law is under some strain, if not in flux.  We clearly disagree about the strength and prominence of various legal positions being defended in those contexts, which is no surprise in light of what I just said.  But Corten quickly reverts to a discussion about whether I’ve sufficiently characterized the nuance of what he calls ‘restrictive’ versus ‘extensive’ interpretations of self-defence.  To me, the most interesting point about this disagreement is how quickly the discussion shifts back from one about doctrinal form to one about substantive permissiveness.  This tendency, to not take doctrinal form – such as bright-lines versus flexible standards – seriously as an independent variable, is precisely why I wrote this article.  I believe we should, and argue in Parts IV and V that perhaps we can, achieve restrictive law with standards rather than rules.  Call me a ‘reformist-Balancer.’

 Third, and finally, Corten emphasizes that what he calls the ‘restrictive’ approach (which I argue tends to correlate very highly with a preference for bright-line rules), strives to achieve “universal inter-subjectiv[e]” validity of legal conclusions.  This is a good way of putting a point many Bright-Liners make, either explicitly or implicitly.  As I explain in Part IV, different orientations toward doctrinal form often reflect assumptions about what is required for international law to function effectively:

Bright-Liners might be especially concerned about the slide from objective standards to unrestrained subjectivity with respect to international legal regulation of military force because there is no single ‘reasonable state’ akin to the hypothesized ‘reasonable person’ of many domestic law contexts. Vast disparities in power, wealth, prestige, interests, and political systems make it impossible to discern a single, universal standard. (p.173)

In contrast to Bright-Liners’ insistence on clear lines likely to give rise to broad consensus as to the lawfulness or unlawfulness of specific instances of force, Balancers are comfortable with a legal regime that does not always, or even often, produce black and white answers. They recognize that many uses of force may fall within some grey area, but that the shade of grey matters quite a lot. (p.175)

 Corten points out that such a view by Balancers probably finds support mostly among English-speaking western powers.  I agree.  Indeed, I make the point throughout the paper that preference for bright-line rules versus flexible standards reflects power politics and disparities in military strength and security vulnerabilities.

 Again, I thank Prof. Corten for his critiques, which have clarified some important points and illustrated some others.