Symposium: Kontorovich Reply to Guzman

[Eugene Kontorovich is a Visiting Professor at Northwestern University Law School and a contributor to the Opinio Juris On-line Symposium]



I would like the thank Peggy and the rest of the Opinio Jurists for providing this forum for the discussion of new work. I’m grateful to Andrew Guzman for providing comments, and even more grateful for providing charitable ones.



Andrew’s comments raise several important issues about the paper and its limitations.



1. Multifactor tests.



I never thought I’d be guilty of multi-factor tests, but Andrew has caught me red-handed. The kinds of social context that lead welfare maximizing norms can be described, but reduced to an algorithm. Rather than an open-ended multi-part test, what the article may suggest is a flipped presumption. International law is based on strong presumption that customary practices of states lead to desirable norms. Without this presumption, we have no reason to reflexively adopt custom across the board. Once this presumption is dismissed and we are considering whether to adopt particular customs a la carte, we are already in a whole different world. That choice is difficult, but the very notion that such choice makes sense is what I hoped to get at.



Finally, perhaps the most important component of efficient-custom situations is the most easy to get a handle one – the question of whether states are likely to be on both sides of an issue over time.



2. Structural adjudication and the alternatives to custom.



The biggest question this paper runs in to is what the alternative to custom is and whether it is likely to be any better. In private law, custom is selectively incorporated by courts, based on something like the multifactor test just mentioned. If a court rejects a customary norm, it provides its own alternate rule. Of course, international law does not generally get made through courts.



Still, there may be some room for structural “adjudication” with the latter term broadly defined. The way I conceptualize customary international law – and this is going far outside the scope of the article – is that in IL “case” is a situation that arises between nations that is understood to be potentially within the scope of international law. The “original ruling” is made by the states themselves through their choice of action; and whether that ruling is subsequently followed or overruled depends on the reactions of other states. In this model, structural adjudication can be done by the states when choosing to follow a customary norm or not. There is an obvious self-judging problem here, but it is endemic to international law and perhaps offset by reputational or other sanctions.



3. Other grounds for international norms.



The argument of custom is that something should be done because everyone does it. On its face, this seems like childish mimicry. But Hayek and others have shown how in certain circumstances, the thing which winds up over time as the custom is welfare maximizing, though none of the participants in the process may see why or how.



This is the structure of an argument based on custom:

1. Everyone/lots of others have stopped doing x; it seems not doing x is a new custom.

2. Customary behaviors are generally efficient [thus we should not be deterred by an impression that not doing x is unwise].

3. Thus we should stop doing x.

If the major proposition (#2) is false, then arguments to adopt a norm because everyone else has loose much of their force. And such arguments are often made in relation many humanitarian norms, such as the death penalty, to take a prominent example.



Does this mean international humanitarian norms should be disregarded? Not at all. They just require a justification not rooted in practice, but in absolute notions of justice. Indeed, this may help humanitarian law. One need not be embarrassed by the disconnect between practice and theory with such well-established norms like torture, because “custom” was never an adequate basis for them in the first place. Thus those who wish to convince a state to adopt a norm should make a substantive case for the norm itself, rather than point to its customary status.