Codifying decentralized forms of law, such as the common law and customary international law, has been a cornerstone of the positivist turn in legal theory since at least the nineteenth century. Commentators laud codification's purported virtues, including systematizing, centralizing, and clarifying the law. These attributes are thought to increase the general welfare of those subject to legal rules and therefore to justify and explain codification. The literature, however, overlooks codification's distributive consequences. In so doing, it misses a common motive for codification: to define legal rules in a way that advantages individual codifying institutions, regardless of how it affects the general welfare.
This Article fills the gap in the literature by examining three rationales for why states codify customary international law: (1) a desire to clarify the substantive content of customary law in order to promote cooperation (the Clarification Thesis); (2) a desire to enhance compliance through mechanisms such as monitoring, enforcement, and dispute-resolution provisions (the Compliance Thesis); and (3) a desire to define the content of customary rules for a state's individual benefit (the Capture Thesis). While codification's proponents conceive of the enterprise in terms of the Clarification and Compliance Theses, I argue that states frequently use codification to capture customary international legal rules to benefit themselves at the expense of the general welfare. As states with divergent views on how to interpret a customary rule pursue conflicting codification efforts, they entrench schisms in the law along regional or ideological lines, thereby delegitimizing customary rules and increasing fragmentation. Thus, far from being an unqualified boon to benevolent legal ordering, codification can replicate, magnify, or alter the power dynamics present in forming bare customary law. Indeed, the fragmentation of customary law that can result from codification actually prevents a unified understanding of customary law from emerging--the exact opposite of codification's ostensible purpose. This Article uses the Capture Thesis to explain important developments in customary international law, including the outlawing of the slave trade in the nineteenth century, the rise of bilateral investment treaties, and the inability to reach an agreement on a multilateral investment treaty.
INTRODUCTION I. THE CONCEPT OF CODIFICATION II. APPROACHES TO CODIFICATION A. Clarification B. Compliance III. THE CAPTURE THESIS A. The Intuition B. Codification as Commitment 1. Commitment 2. Piracy and the Outlawing of the Slave Trade C. Codification and Procedural Rules 1. Procedure and the Codification of Customary Obligations 2. Procedure in the Amendment of Codified Customary Obligations D. Treaty Membership E. Conclusion IV. RAMIFICATIONS A. Suboptimal Rules B. Fragmentation 1. How Codification Leads to Fragmentation 2. International Investment Law as Fragmented Codification a. The Codification of the Calvo Doctrine b. International Investment Agreements and the Failure to Reach a Multilateral Investment Agreement C. Conclusion CONCLUSION INTRODUCTION
In 2004, the World Trade Organization (WTO) abandoned its most recent effort to reach a multilateral agreement governing investment. (1) Such efforts have been part of an on-again, off-again push by developed countries to codify and harmonize international investment law, with the goal of reducing barriers to international capital flows and facilitating regional integration in places like North America and Europe. Developed states have pushed for a multilateral agreement since the end of World War II and indeed produced draft conventions in 1948, 1967, and 1998. (2) But none of these draft conventions has gained traction. With efforts at the WTO unsuccessful, trade in capital remains the key pillar of international economic law still largely outside the purview of WTO disciplines. International investment law thus remains governed by customary international law and the "spaghetti bowl" of bilateral, regional, and sectoral agreements that partially codify investment law.
This pattern of failure is puzzling. States long ago agreed to a robust set of multilateral rules governing trade in goods and services. They reached these agreements despite a relative lack of preexisting multilateral law on trade liberalization and protection, at least when compared with investment law. Prior to the 1947 General Agreement on Tariffs and Trade (GATT), (3) for example, there was little multilateral law in the area of trade barriers; prior to the 1994 General Agreement on Trade in Services, (4) there was little independent law on trade in services.
Prospective codifiers of investment law, by contrast, have a wealth of sources on which to draw for their multilateral codification efforts. For at least a century, customary international investment law has provided a multilateral legal standard governing the protection of property owned by aliens. (5) Moreover, the explosion of bilateral investment treaties (BITs) and similar regional and sectoral investment agreements--the structure and content of which are similar across the roughly 2600 agreements in force--have reinforced preexisting customary law and created a type of multilateral regime that reaches most states in the world. (6) Yet as the many efforts to negotiate a viable multilateral investment agreement at both the WTO and the Organisation for Economic Cooperation and Development (OECD) attest, states do not view this patchwork of treaties with limited membership and customary law as an adequate substitute for a truly multilateral convention.
What, then, explains the failure to reach a multilateral agreement on investment? I argue that this failure is part of a larger phenomenon in which codification--by which I mean the process of reducing law to a written instrument that elaborates established customary doctrines--can actually interfere with the development of truly global governance. Specifically, I contend that states often use codification to capture customary international legal rules to benefit themselves at the expense of the general welfare of the global community.
This suggestion may seem radical: the codification of customary international law--along with the rise of international organizations, one of the pillars of the twentieth century movement toward legalization in international affairs--has been a part of the legalization project since the late nineteenth century. (7) Spurred by the rise of legal positivism and a desire to avoid the pan-European and global conflicts that marred the nineteenth and early twentieth centuries, states convened major codification conferences in 1899, 1907, and 1930. (8) After World War II, the U.N. Charter explicitly tasked the General Assembly with the development and codification of international law as a means of promoting international cooperation, (9) a job the General Assembly has largely delegated to the International Law Commission (ILC). Moreover, codification continues to occupy a central place in contemporary international legal practice. Since 1990, states have codified or have tried to codify customary rules of investment law in negotiations at the WTO and OECD, (10) international criminal law in the Rome Statute of the International Criminal Court, (11) and customary norms of environmental protection in a variety of regional and global agreements. (12) The wars in Iraq and Afghanistan have highlighted customary law on the use of force and its exceptions, as codified in the U.N. Charter. Furthermore, the treatment of detainees in the war on terror has brought to the fore the customary international law on the treatment of prisoners, as codified in the Geneva Conventions, (13) and the ban on torture, as codified in the Convention Against Torture (CAT). (14)
The conventional wisdom is that states codify customary law to clarify the law and promote compliance. Claims that codification clarifies the law, in particular, are legion. (15) According to these arguments, codification allows states to specify more precisely what customary international law requires, thereby facilitating deeper cooperation and avoiding costly disputes over vague legal rules. (16) Codification also introduces the possibility of attaching compliance-promoting mechanisms--such as protocols granting international tribunals jurisdiction over disputes--to customary rules. (17) Such mechanisms increase sanctions for violating the law and are thereby thought to boost compliance rates.
These rationales, which I refer to as the Clarification and Compliance Theses, only partially explain the allure of codification. Both the Clarification and Compliance Theses focus primarily on efficiency. They suggest that states will take actions that increase overall global welfare. For example, all else equal, agreeing to submit disputes to a tribunal should boost compliance by exposing violations. But rational states generally are interested first and foremost in increasing their own welfare. Increasing overall welfare is merely a means to that end, since it increases the size of the pie to be divided. For states to do what is in the interest of overall welfare thus requires certain assumptions about interstate bargaining--such as low transaction costs--which will often not hold in the real world.
I therefore introduce what I call the Capture Thesis of codification. (18) I argue that codification is often driven by distributional concerns, rather than efficiency concerns. States seek to codify customary rules that benefit their interests as a way to define and capture those rules. Codifying customary rules is an attractive strategy because it allows states to influence the content of rules that bind all states without having to negotiate a universal treaty, with all the costs and compromises such negotiations entail.