A seasoned practitioner of international law once commented that states do not like their intention to undertake a particular commitment to be a surprise for them. But a careful observer of the life cycle of treaties would be tempted to paraphrase Michel Foucault’s famous statement about intentionality in power relations and point out that when undertaking treaty commitments, states ‘know what they do; they frequently know why they do what they do; but what they don’t know is what what they do does’. Indeed, international law is replete with examples of international legal commitments being expanded in practice in ways that could not have been contemplated by the states that undertook those commitments.
This state of affairs neatly illustrates the puzzle of consensualism in international law. On the one hand, it is widely recognized that state consent plays a foundational role in international law. On the other hand, there is limited understanding of what role consent plays in the actual operation of international law. Most existing accounts of consent are largely confined to the notion that states are not bound by international law without their consent. What it is that states are specifically bound by and whether and to what extent there is room for any ‘substantive consensualism’ constraining the determination of the content of their commitments remains severely undertheorized. In an era of international regulatory agreements and increasing judicialization of international affairs, this gap is not merely intellectual; it entails serious consequences, including the legitimacy deficit of international law, state resistance and uneven distributional consequences in a world of unequal resources. As a result, the existing accounts of consent face a twofold crisis: firstly, they cannot account for expansion of treaty commitments, and; secondly, they relegate ‘substantive consensualism’ to the backseat, supplying ammunition for pushback and backlash against international law.
The project aims to fill this significant research gap and initiate a new way of thinking about consent in international law. Its working assumption is that the intellectual matrix and the operating structures of international law governing treaties came into being long before important developments in treaty making, the rise of international regulatory agreements and independent third party mechanisms. While classic treaties were merely transactions among chancelleries involving little more than state diplomatic machineries, most modern treaties are tools of global governance affecting numerous actors and allocating public goods and having third parties, rather than the parties to those treaties, as their exclusive or primary beneficiaries, placing significant strains on the traditional understanding of consent. Existing doctrinal accounts of consensualism also sit uneasily with independent compliance mechanisms, the latter typically having the upper hand in the competition for authority to determine the content of treaty commitments in a system in which impartial and independent statements of law are relatively rare and highly valued.
The alternative framework that the project seeks to offer aims to explain how treaty commitments are developed in practice while the ideological and rhetorical commitment to the principle of consensualism is kept intact. In particular, it attempts to identify patterns in the discursive expansion of international legal commitments by paying close attention to the main tropes, informal understandings and arrangements, discursive protocols, rules and constraints governing the administration of international legal commitments in the perception of international legal operators. The findings are expected to make significant contribution to the literature in international law and beyond, notably by supplying students and actors of global governance with analytical tools to better appreciate the power and limits of consensualism in international law and to design and communicate about treaty commitments more efficiently.
Timeline: October 2025 - August 2029.
Funding organisation:
