Linos Book Symposium: Comments by Eric Posner

[Eric Posner is Kirkland & Ellis Professor of Law and Aaron Director Research Scholar at the University of Chicago]

I’m going to focus on a narrow issue, one that Katerina takes up in the last chapter of her impressive book, and that is the relationship between policy diffusion (the topic of her book) and international law (which is something of an afterthought), and specifically the debate as to why states comply with international law. I can see a few possibilities.

First, there is no relationship between the argument in her book and international law. Katerina argues that state X may adopt the policies of state Y because voters in X perceive the success of the policy in Y as evidence of its value, but this process of diffusion says nothing about why state X may comply with an agreement with state Y. Suppose, for example, that state X and state Y enter into a mutual defense pact. The fact that X may imitate Y’s domestic policies, or even foreign policies, does not mean that X will comply with the pact.

Second, the book suggests that international law is weaker than generally recognized. Maybe what appears to be compliance with international law because it is law is actually the diffusion of policies. X and Y agree to reduce tariff barriers but X lowers its barriers not because of its treaty but because Y, for independent domestic reasons, lowers its barriers, and X mimics Y. Policy diffusion, not international law, is the causal factor. Thus, if numerous other states raise their trade barriers, we would expect X or Y to raise their trade barriers as well, in violation of the agreement.

Third, states comply with treaties because the treaties themselves become a vehicle for the diffusion of policy. States X and Y enter the WTO and comply with its rulings in order to obtain gains from trade. State Z can more easily imitate X and Y’s policies by observing the WTO’s rulings than by surveying numerous states. If Z is itself a member of the WTO, then policy diffusion here may in some sense cause Z to comply with the WTO, or at least act consistently with it. Note, however, that according to Katerina’s argument, Z would comply with the WTO rulings even if Z were not a WTO member and thus had no legal obligation to do so.

Katerina endorses the third hypothesis, but her evidence does not distinguish it from the other two. This matters when we consider her claim that her thesis and evidence should quiet those who criticize international law because it interferes with democracy by constraining domestic politics. Katerina’s argument that international law generates information that voters can use to discipline their political agents depends on an implicit assumption, never defended, that policy differences across states are mainly due to asymmetric information, and not heterogeneous values and preferences.

There are three problems with this assumption. First, people in different countries really do have different values and interests; no amount of information-sharing will overcome differences between fundamentalist Muslims in Karachi and secular Jews in New York City. Much of international law is designed to create workable compromises between people who might otherwise be inclined to kill each other. When two countries settle a border dispute or agree to reduce arms, they benefit through mutual constraint. Their activities have nothing to do with policy diffusion.

Second, policy diffusion itself is a more ambiguous phenomenon than Katerina lets on. When state X adopts the policies of state Y, it can be difficult to distinguish between learning and mere herd behavior. In the case of herd behavior, no information is shared. International organizations that set standards may, as Katerina argues, help spread valuable information, but they may also create uniformity across countries that does not serve the interests of diverse populations. When one considers the history of policy diffusion, one should not neglect the spread of communism and fascism, or—if you want—imperialism or neoliberalism. Bad policies diffuse just as effectively as good policies do. Indeed, beyond this, Katerina does not show that international policy diffusion is a significant phenomenon, as she selects on the dependent variable, as empiricists like to say. How many policies are not imitated?

Finally, one ought to distinguish between a country nominally adopting a policy and actually implementing it. Katerina focuses on developed countries, and it is reasonable to assume for such countries that legislating a policy like a national health system is the same as implementing it. But the governments of many countries (particularly, poor countries) pass legislation or issue decrees in which they imitate the policies of western countries but do not implement them, often because they lack a competent bureaucracy or independent judicial system that enforces the law. Ratification of human rights treaties, sometimes leading to sham constitutions or empty legislation, is an important example.