What if ATS Liability has Nothing to do With “Customary” International Law? Part I

by Harlan Cohen

Much of my work focuses on international sources theory, not exactly the material for a scintillating, timely blogpost, and I initially thought I should probably spare you my thoughts on it.  (As a footnote, an early draft of my entry-level job talk paper was titled, “Taking Opinio Juris Seriously.”  I understand this had some of the OJ members on hiring committees pretty excited – Vindication! – at least until the read the piece…)  But then came the cert. grant in Kiobel, the Ninth Circuit’s decision in Sarei v. Rio Tinto and the debate on this blog about Doe v. Nestle.  Could international law theory suddenly be current and relevant?  Suddenly, there seemed a timely argument for getting international law sources doctrine right.

For me, the most striking thing about the discussion on this blog regarding corporate and aiding and abetting liability under the ATS was the assumption by almost all that, at least at the international (rather than domestic law) level, this was a matter of customary international law.   This appeared to be the case for both those who thought custom supplies standards on these issues and for those who think it has not yet fully developed.  But is this at all obvious?  There seems to be a reflexive assumption in international law that if a rule seems to be treated as law and is not in a treaty, then it must be custom (or perhaps, a general principle).  Why?  Well, because Article 38 of the ICJ Statute gives us no other options.  But in figuring out whether something is custom, it’s not enough to know that the rule is not in a treaty.  We need to actually test it against the concept of customary international law.

As Sasha Greenawalt suggested in a comment and elsewhere, it’s hard to imagine how the standards for corporate or aiding and abetting liability could meet this test.  The basic idea behind customary international law is that law can emerge from the customary practice of states in their relation to one another.  But how could or would states develop a customary practice with regard to these issues?  The issues are unlikely to come up in interstate conflicts and settlements.  Perhaps we’d find some generalized recognition of aiding and abetting liability or liability for corporate entities in the resolution of such disputes, but it is hard to imagine any clear standards emerging through their negotiations.  How would mens rea, for example, even come up?  Nor can we really say that these rules are emerging from the practice of states with regard to international criminal tribunals or trials.  Very few states have been involved in these processes, and where they have been, they’re often acting as official or de facto prosecutors or defendants – states may suggest standards that should apply based on their position in the case, but it is a court that decides whether to accept that position or not.  Given this reality, it should not be surprising that the ICTY, ICTR, and other modern criminal tribunals cite the decisions of other international or pseudo-international courts (particularly of the Nuremberg era) or even domestic courts, rather than the practice of states.  If we really want to talk about custom, “court custom” seems to be a better description, but if that’s the case, we’re no longer really talking about customary international law as traditionally understood.  Courts may say that what they’re developing here is customary international law, but what really seems to be emerging in this area is a form of international common law.  Courts, by necessity, fill the gaps in the law that otherwise wouldn’t or couldn’t be filled.

It’s not that we can’t come up with an argument that the jurisprudence of these courts has become custom – we’re good lawyers of course.  Perhaps we might argue that these decisions have been ratified by custom in states failure to object.  Or perhaps we would argue that recognition of some of these standards in the Rome Statute of International Criminal Court evidences their broad acceptance.  The first argument though stretches the notions of customary practice and consent close to their breaking points.  The second would face the challenge that the Rome Statute was a particular treaty explicitly negotiated for a particular purpose.  Both descriptions of how aiding and abetting or corporate liability standards operate as law are far more attenuated and far less convincing than the possibility they are part of an emerging international criminal common law.

This does not mean that these rules are not international law, nor that if not custom, they’re not cognizable under the ATS.  In fact, in the next post, I’ll argue that understanding these rules as a form of international common law actually helps clarify the ATS analysis and the role international criminal jurisprudence should play.


5 Responses

  1. I hope that Professor Cohen will address the natural law of nations, its express recognition in treaties (e.g, Treaty of Ghent, Treaty of Paris, Hague Convention, Geneva Convention Prot. 1), and its relationship to international tribunal competence to decide cases ex aequo et bono.

    Francisco Forrest Martin

  2. My sense is that this is really a general anxiety about the customary international law of criminal norms generally.  International criminal lawyers always talk about customary international law, and it is a bit unclear what they mean, and there is some slippage between precedent/case law and customary norms.  The one doesn’t necessarily imply the other.
    Simply put, CIL requires state practice + opinio juris, and in most cases criminal norms are not applied with a reciprocal sense of legal obligation (though some recent human rights constraints on criminal procedure may indeed stem from a sense of legal obligation).  But substantive criminal norms rarely do (though it is possible).

    However, I’m unclear on what the rub of this argument is for purposes of ATS liability under Sosa.  ATS liability only requires a violation of the law of nations, not a violation of CIL.  So determining the correct category establishes the ground rules for what counts as a violation, but the category of violations under Sosa is, of course, much larger than simply CIL.

  3. Thanks Jens.  We’re in complete agreement, as I think Part II of this post will show.  I would actually argue that the anxiety goes far beyond international criminal law, and reaches almost every area where authoritative or semi-authoritative bodies are tasked with developing international law rules in order to answer specific questions before them.

    Francisco, I actually have a strong interest in looking back at historic international law paradigms and in some cases even reviving them, something I may blog about later.  I’m not sure though what exactly you’re getting at here in this context.  Could you say more?

  4. Prof. Cohen:

    You may want to take a look at these issues that I briefly discuss in my book, THE CONSTITUTION AS TREATY (Cambridge Univ. Press 2007) beginning on pg. 100.  I was hoping that someone — such as yourself — would expound more (than I have) on the natural law of nations and its relationship to positive legal and judicial subjects.

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