What Should the Restatement (Fourth) Say About Treaty Interpretation

At the end of the drafting of the Restatement (Third) of the Foreign Relations Law, one observer joked that the Restatements should be titled like serial westerns-"something like Restatement, Return of the Restatement, Son of the Restatement, and the Restatement Rides Again."1 As with all good analogies between law and popular culture, this quip is ridiculous and yet somehow right. To be sure, there is little of the lone rider in a Restatement. Instead, each Restatement is the product of a byzantine institutional process involving reporters, counselors, advisers, the ALI Council, and the ALI membership, as the immense number of drafts will attest. But the quip has a ring of truth. There is something undeniably heroic about the Restatements. They tower over most other private contributions to the understanding and the development of law.With the Restatement (Fourth) of the Foreign Relations Law now on horse-though still far from the sunset-comes the scramble to influence its course. Like others, I have a wish list. Mine includes as narrow treatment as possible of some recent supreme Court decisions relating to treaties and an emphasis on process-based flexibility for the political branches.2 For purposes of this symposium, however, I wish to focus on a single issue: the legal principles that should govern the interpretation of treaties by U.S. courts.Two core questions underlie treaty interpretation by U.S. courts. First, what legal principles govern the interpretation of treaties? Second, to what actors, if any, should deference be given with regard to treaty interpretation? Each of these questions potentially has both international and domestic legal dimensions. The Restatement (Second) and Restatement (Third) both addressed these questions, but, as I detail here, they did so against quite different backdrops than are present today. Since the Restatement (Third) was finalized in the mid-1980s, there have been shifts both in international law on treaty interpretation and in U.S. domestic practice regarding treaty interpretation. The Restatement (Fourth) should ideally structure its provisions on treaty interpretation not only to reflect these developments, but also to situate them analytically in ways that further the "clarification and simplification of the law and its better adaptation to social needs."3 I argue here that the most important way to do so would be to incorporate the full text of Articles 31 and 32 of the Vienna Convention on the Law of Treaties ("Vienna Convention") into the black letter of Restatement (Fourth). In addition, I offer some thoughts on how the Restatement (Fourth) should approach the issues of deference and of the interpretation of statutes related to the implementation of treaties.I. HOW THE RESTATEMENTS (SECOND) AND (THIRD) DEALT WITH TREATY INTERPRETATIONThis Part describes the choices about treaty interpretation made in the Restatement (Second) and Restatement (Third) and sets them in the context of the times in which these Restatements were drafted. Doing so sets the stage for considering the prospects for change and continuity in the future Restatement (Fourth).A. Restatement (Second)The original plan of study for the Restatement (Second) did not include treaty interpretation among its topics.4 It was quickly added, but mainly because of an interest in the domestic legal question of whether U.S. courts owed deference to the views of the executive branch.5 By contrast, Reporter Adrian Fisher initially considered the international law on treaty interpretation to be a topic on which the Restatement would not add particular value.6 As the project developed, however, it came to encompass both international and domestic legal considerations in relation to treaty interpretation.As to the international legal principles of treaty interpretation, Section 147(1) of the Restatement (Second) identified the overall aim to be "ascertaining] and giv[ing] effect to the purpose of the international agreement. …