The Vienna Convention on the Law of Treaties in U.S. Treaty Interpretation

Abstract

The Vienna Convention on the Law of Treaties has been widely recognized as the authoritative guide to the customary international law governing treaty interpretation. In American courts, however, the Vienna Convention has enjoyed a mixed reception. Since the Convention entered into force in 1980, the Supreme Court has never cited the Convention for a controlling rule of decision, choosing instead to rely upon nationalist common-law canons developed by analogy to domestic contract law. By contrast, many lower federal and state courts have adopted an overtly internationalist approach to treaty interpretation, applying the Vienna Convention's treaty-interpretation provisions as customary international law. This methodological divide is significant, because the Vienna Convention's interpretive canons depart from the Supreme Court's common law canons in at least three critical respects: First, the Vienna Convention does not contemplate recourse to domestic ratification materials. Second, although the Vienna Convention discourages courts from deferring to a single state's unilateral treaty interpretations, the Supreme Court preaches deference to executive branch treaty interpretations — even in the face of conflicting interpretations from other treaty parties. Third, courts applying the Vienna Convention are less receptive to arguments that treaty provisions should be construed in derogation of the United States' other obligations under international law. Whereas the Vienna Convention views municipal courts as participants in a transnational community of courts, the nationalist paradigm envisions domestic courts as agents of national sovereignty with an obligation to maximize the United States' immediate strategic interests. To bridge the tensions between these competing traditions and place U.S. treaty jurisprudence on a more coherent and sustainable foundation, this article argues that domestic courts should invoke the Vienna Convention more expressly and employ its canons more systematically in deciding questions of treaty interpretation.

Keywords: treaties, interpretation, Vienna Convention