Cheng Book Roundtable: How to Assess the Value of International Legal Theory

I agree with Professor Cheng that legal theory does not have to be predictive to be successful.  But I wonder if he sets the bar a bit too low. In his previous post, he writes:

Providing a framework of analysis to address international problems, to guide but not control, is perhaps the best that can be done. It may also be the most that ought to be done.

But two of the leading alternative theories that Professor Cheng discusses in his book claim to do more than simply guide. One, positivism, claims to control and the other, rationalism, claims to predict.

In the waterboarding example, as Professor Cheng acknowledges, positivists have a simple assessment: the law prohibits all waterboarding as either torture or cruel and unusual punishment.  In almost all cases, therefore, decisionmakers will adhere to these norms.  Positivists will then cite the vast majority of the cases where the norm is adhered to, and suggest the U.S. example was aberrant.

Rationalists claim that their theory is more predictive than positivism, since it can explain why countries will sometimes obey, and sometimes do not obey, international law. Indeed, this is one of the great virtues of rationalism over positivism, since it claims to be a description of the way the world actually works, and it notes that its description is more accurate (and predictive) than positivism.

Professor Cheng’s theory is open to the criticism that it is both less descriptive and less predictive that either of its chief rivals.  The reason for this is that it relies on a highly contextual model of analysis that we might describe, in legal terms, as highly fact dependent.  Without facts and specific context, he seems to be arguing, it is not possible to predict an outcome, nor would it be responsible to do so.

It seems, then, that the foundation of Professor Cheng’s theory is really normative, and not descriptive. But what exactly is the normative case? What makes this theory normatively more attractive than other theories?  Given its highly contextualized approach, how will we know whether it is achieving “better” or more desirable results?

It is here where I meant to use the “moderate” description.  Not to describe Professor Cheng, exactly, but describe how he positions the policy-oriented approach as a moderate position between positivist and rationalist extremes. I find this, as a matter of politics and policy, compelling.  But it remains, I think, a pretty dissatisfying basis for adhering to a theoretical approach.