Applying rational choice theory to customary international law: Enrichment or impoverishment

The standard positivist account of customary international law is under siege. In a pair of recent influential articles, Jack Goldsmith and Eric Posner employ rational choice theory and assert that customary international law plays little or no role in decisions by states. They argue that customary international law emerges from the pursuit by states of their self-interested policies on the international stage. Professors Goldsmith and Posner purport to substantiate their thesis by examining the state practices associated with four supposedly well-settled rules of costomary international law. This dissertation evaluates rational choice theory's potential for illuminating customary international law and refutes Professors Goldmisth and Posner's conclusions. Contrary to Professors Goldsmith and Posner's claim, rational choice theory does not (indeed cannot) offer a comprehensive or exclusive picture of customary international law; the theory's sights have been set too high. States may rationally pursue ends that defy simple modeling. Moreover, norms may also have a substantial role to play. Professor Goldmisth and Posner's "empirical" claim is equally suspect. Their selection of episodes involving customary international law is highly tithed so as to support their ultimate conclusion. This dissertation demonstrates that Professors Goldsmith and Posner omit many other important controversies in which arguments about custom have exerted considerable influence.