Do International Agreements Have a Consent Problem?

Abstract

This chapter explores how consent functions as commitment, content, and constitution for international agreements. First, consent constructs all forms of international commitment, not just those governed by international law (treaties), but those governed by national law (contracts) and those not governed by law at all (political commitments). Second, consent elucidates an agreement’s contents – what the agreement "is" in terms of both its scope and substance. Third, consent can function as a constitution – delimiting not only those "primary" rules encapsulated by an agreement’s existence and contents, but also providing the basis for its "secondary rules," determining who can make agreements, how they must do so, and the ways to recognize, adjust, or end them.

For all these functions, consent remains an under-examined and undifferentiated concept in both international law and international relations. Today, almost any of consent’s functions can be established by almost any formal or informal means. This leaves ample room for inconsistent understandings, unaligned expectations, and disputes about the existence of treaties and other forms of international agreements, their contents, and their relevant constitutive rules.

This chapter surveys the different functions consent serves for international agreements and the problems that its ubiquity and polysemy may pose. It explores existing proposals to redress such challenges, including the use of presumptions, defaults, and content-based criteria. I call for more descriptive and normative attention to this topic, and introduce a new solution: having international law pursue more—and different—formalities for consent. Having different forms of consent follow its different functions could improve the efficacy of consent itself and with it the efficacy of international agreements overall.

Keywords: consent, international agreement, treaty, political commitment, non-binding agreement, contract, treaty-making, formalities, intent, will, interpretation, amendment

JEL Classification: K33