International Organization

The book, a collaborative effort by three leading scholars, does not simply ask what the rules governing IOs are, but why they are structured that way and what this implies for the future of global governance. Its relevance is undeniable in an era where IOs like the UN, WTO, and WHO are increasingly powerful yet face crises of legitimacy, accountability, and effectiveness. Understanding the constitutionalization thesis is key to analyzing contemporary legal debates, from the Security Council’s sanctions regimes to the judicial authority of the European Court of Justice and the dispute settlement mechanism of the WTO.

This book provides the necessary theoretical background to critically assess whether international law is evolving into a more coherent, hierarchical, and value-based system or if it remains a fragmented set of contractual rules between states.

Summary

The book is structured as a series of interconnected essays, each authored by one of the writers, exploring different facets of the constitutionalization phenomenon.

Klabbers opens by defining the concept. He argues that constitutionalization refers to the process whereby international law is moving from a state-centric, consent-based model (like a contract) towards a more public law-oriented, community-based model (like a constitution). Key features of this shift include the emergence of jus cogens (peremptory norms), erga omnes obligations (owed to the international community as a whole), and the increasing importance of institutions that apply law autonomously.

Peters focuses on the substantive elements of constitutionalization. She explores how certain fundamental values, such as human rights, democracy, and the rule of law, are becoming foundational principles of the international legal order. She analyzes how these principles penetrate the institutional frameworks of IOs, potentially limiting their powers and subjecting them to higher standards of accountability. For her, the proliferation of international judicial bodies is a key driver of this process, creating a web of checks and balances.

Ulfstein examines the institutional dimension, particularly the law-making and adjudicative powers of IOs. He investigates how entities like the UN Security Council, with its Chapter VII powers, and judicial bodies like the ICJ and WTO panels, exercise authority that has profound constitutional implications. A major theme is the concept of “delegated power”: IOs derive their authority from states, but this authority can evolve and expand in practice, leading to questions about who controls the controllers.

The book’s main argument is that these three strands—institutional growth, the entrenchment of substantive values, and the development of hierarchical legal norms—are intertwining to form a nascent constitutional structure for the global community.

Critical Analysis

Strengths:

The book’s primary strength is its compelling and cohesive theoretical framework. It successfully provides a vocabulary and a set of concepts (“constitutionalization,” “community interest,” “delegated authority”) that allow for a sophisticated analysis of seemingly disparate developments in international law. For example, it connects the dots between the European human rights regime, UN sanctions, and WTO law under a single analytical umbrella.

Another significant strength is its balanced approach. The authors are not mere evangelists for constitutionalization; they are its critical proponents. They meticulously acknowledge the weaknesses and contradictions in the process. Klabbers, in particular, is cautious, noting that the language of constitutionalism can be used to mask hegemonic power politics or to legitimize IOs that remain fundamentally undemocratic. This self-critical lens elevates the book from a polemic to a serious scholarly inquiry.

Weaknesses:

The book’s main weakness, acknowledged by the authors, is its inherent ambiguity. “Constitutionalization” is a contested and fluid concept. Critics like J.L. Goldsmith and E.A. Posner would argue that the international system lacks the centralised coercive authority, democratic pedigree, and social cohesion necessary to be labelled “constitutional.” The book demonstrates the trends but cannot definitively prove that a full-blown constitution exists. This can sometimes make the argument feel more aspirational than descriptive.

Furthermore, the book’s focus is largely on Western led institutions and liberal values. It pays less attention to how this constitutionalization process is viewed by emerging powers or non-Western states, who might perceive it as a form of normative imperialism that restricts their policy space and sovereignty.

Contribution:

Despite these weaknesses, the book’s contribution is immense. It provides a powerful narrative for understanding the evolution of international law. It moves the discourse from “whether IOs have legal personality” to “how the authority of IOs should be constituted, controlled, and legitimized.” It forces the reader to confront essential questions about accountability, the common good, and the very nature of law in a globalized world.

Application

The constitutionalization thesis is not an abstract theory; it is directly applicable to pressing legal debates and cases.

Case Application: Kadi v. Council of the European Union (2008)

This case is a quintessential example of the clash between legal orders that constitutionalization theory predicts. The UN Security Council, acting under Chapter VII, imposed sanctions on individuals suspected of terrorism. The European Union implemented these sanctions. Mr. Kadi challenged the EU regulation at the European Court of Justice (ECJ), arguing it violated his fundamental human rights (to a fair hearing, to effective judicial review, to property). The ECJ annulled the regulation, asserting the primacy of the EU’s constitutional principles of human rights over the UN Security Council resolution. This case perfectly illustrates Peters’s point about substantive values (human rights) acting as a constitutional constraint on the power of an IO (the UN). It shows a judicial body creating a hierarchy of norms where human rights trump other international obligations.

Current Issue: The WTO Crisis

The WTO’s Appellate Body, a key institution for the judicial resolution of trade disputes, has been paralyzed since 2019 due to the U.S. blocking the appointment of new judges. From a constitutionalization perspective, the Appellate Body was a engine of judicial law-making, developing a body of jurisprudence that member states were bound to follow. Its crisis represents a powerful counter-argument to constitutionalization a stark reminder that the process is fragile and reversible. It demonstrates that powerful states can and will withdraw their consent when they perceive that an IO, through its judicial body, has overstepped its delegated authority and engaged in judicial activism. This connects directly to Ulfstein’s analysis of delegated powers and their limits.

Legal Debate: UN Security Council Reform

The perennial debate about reforming the UN Security Council, particularly its veto power, is a constitutional debate. It is a debate about the foundational structure of global power about representation, accountability, and the limits of authority. The constitutionalization framework asks whether the current setup, where five states have unparalleled power, can be legitimate in a system increasingly based on community values and the rule of law.

Conclusion

Reading The Constitutionalization of International Law was a challenging but immensely rewarding experience. It moved my understanding of international organizations from a static, rule-based perspective to a dynamic, system-level one. I learned that international law is not a finished product but a process of ongoing negotiation, contestation, and evolution.

The key takeaway for me is the inherent tension at the heart of global governance: the tension between the need for effective, powerful international institutions to tackle global problems, and the parallel need to ensure these institutions are legitimate, accountable, and respectful of fundamental rights. The constitutionalization thesis provides the best framework I have encountered for understanding and navigating this tension.

While the book convinced me that constitutionalizing trends are real and significant, it also made me wary of overly optimistic readings. The current state of international affairs, with rising nationalism and challenges to multilateralism, shows that the path towards a constitutionalized order is not linear or inevitable. However, by providing a map of this complex terrain, Klabbers, Peters, and Ulfstein have made an indispensable contribution to the field, one that equips any student of international law with the tools to think critically about the power of the organizations that shape our world.