Treaties, Executive Agreements, and Constitutional Method

Foreign relations law presents a particularly fertile field in which to explore constitutional dynamics. This article uses the recent debate over the constitutional interchangeability of Article II treaties (requiring supermajority approval of the Senate) and congressional-executive agreements (approved with a bicameral majority) as a case study in constitutional method. The article first critiques arguments by Laurence Tribe, who on a textual basis argues the constitutional illegitimacy of the North American Free Trade Agreement and the World Trade Organization Uruguay Round, both approved as congressional-executive agreements; and by Bruce Ackerman and David Golove, who assert their constitutionality in all cases as grounded in a constitutional moment following World War II. This article argues that the constitutionality of congressional-executive agreements can be established, but only at the end of an accretive historical practice and only in a narrow range of substantive contexts. In contrast to Tribe, the article demonstrates the constitutionality of congressional-executive agreements; in contrast to Ackerman and Golove, it denies the full interchangeability of congressional-executive agreements with treaties. The article uses post-war developments to show that the congressional-executive agreement form is acceptable in some contexts (with respect to trade agreements, where it may in fact be mandatory) and not in others (most notably with respect to arms control agreements, where the Senate has maintained an institutional opposition to submitting such agreement via any route other than Article II). The article uses this case study to pose a model of constitutional increments. In contrast to the moments approach, the increments model accepts the evolutionary, episodic development of constitutional norms. The model offers four metrics for assessing the constitutional significance of any particular constitutional episode: acceptance by relevant actors, including non-judicial and, in some cases, non-governmental actors; the degree of contestedness evidenced in an episode (the more contested a principle, the greater significance afforded the resolution of that contest); the age of the episode (older episodes being less significant, at least as unsupported by more recent practice); and the pedigree of the principle for which the episode is offered. This model, the article asserts, offers greater constitutional determinacy than competing models of constitutional development. The model also better advances the central normative virtue of constitutionalism, namely of facilitating recognition of long-term community aspirations through the constraint of shorter-term continuity.