This chapter provides a detailed account of the impact that the Commission’s work has had in shaping the Court’s case-law. In addition to surveying and classifying all those instances in which the Court has to date been ready to refer expressly to the Commission’s output, the chapter demonstrates that reliance on the Commission’s work has often been more implicit. The question is then posed as to the basis for such recourse and the advantage afforded by it.

The final chapter looks at the relationship between international and EU law. Also for this relationship it is decisive to, first, clearly identify how the EU can establish a consensus at the larger international level. This implies, on the one hand, that the EU is a subject of international law (Article 47 TEU and Article 335 TFEU) and, on the other hand, that the EU is competent to act concerning the subject matter (Article 3–6 TFEU). As both conditions are clearly satisfied by now, it is necessary to find out which organ is authorized to conclude an international norm (Article 216–219 TFEU). Second, it is important to determine the content of the consensus. This interpretation process is primarily the task of the level at which the consensus has been agreed. This is the international level. Third, this chapter holds that the effect of this consensus on the level of the smaller circle depends on whether the norm of the international circle is solely applicable, directly applicable or individualizing. This is demonstrated in this chapter by looking more closely at how the effect of an international treaty and customary international law unfolds within the EU legal order.

As state ownership of private firms grows, morphs, and globalizes, states increasingly channel their influence through the financialized markets. The ensuing merger of the state’s commercial and sovereign roles suggests that state ownership is, again, becoming a vector of sovereign authority. This chapter analyzes the international legal system that has developed around surging state ownership. It suggests that the legal construction of distinctive “shareholder identities” in international economic law plays a key role in this complex regulatory matrix. Specifically, the chapter focuses on how arbitral tribunals adjudicating claims arising from international investment treaties use attribution, a doctrine of customary international law, in creating, maintaining, and disciplining state shareholders. Arbitral tribunals use the analytical category of the state shareholder in order to delineate and construct state and company identities and to understand the economic, political, and legal implications of those identities in the the global economy. Accordingly, the interactions between substantive international economic law and the law of state responsibility form important, but underappreciated, elements of this constitutive process, which comes to affect the institutional design of state shareholding and disincentivize hands-on control over state-owned entities.

This chapter examines two ways the customary norm could have emerged post-1945: the two-element approach or that article 2(4) gave rise to a new customary rule of its own impact, following the approach of the ICJ in the North Sea Continental Shelf Cases. It demonstrates the challenges of applying the two-element approach to the customary prohibition of the use of force due to the presence of the parallel and near-universal treaty obligation in article 2(4) of the UN Charter, which makes it difficult to identify sufficient relevant State practice and opinio juris outside the treaty. Establishing evidence of the customary rule and its content in this way depends on a number of theoretical issues that remain unsettled or over which significant controversy exists. This chapter then applies the criteria set out by the ICJ in the North Sea Continental Shelf Cases to article 2(4) and argues that article 2(4) meets this test. This chapter concludes that, in contrast to the right to self-defence in article 51 of the UN Charter which explicitly has its origins in customary international law, article 2(4) is itself the origin of the customary international law prohibition of the use of force.

This chapter examines the relationship between the prohibition of the use of force in article 2(4) of the UN Charter and customary international law: if they are identical, the role the customary rule plays in the interpretation of article 2(4) and which one to interpret or apply to determine the meaning of a prohibited ‘use of force’. In doing so it examines the following concepts: the use of pre-existing or subsequently developing custom to fill gaps in the treaty, the use of subsequently developing custom to informally modify the interpretation of the treaty, an evolutive interpretation of the UN Charter and informal treaty modification through subsequent practice. It argues that since article 2(4) is the origin of the customary prohibition, it is not appropriate to use pre-existing or subsequently developing customary international law to fill gaps in interpretation of article 2(4) nor to use subsequently developing custom to modify article 2(4). It concludes that due to the present relationship between the customary and Charter prohibitions, the preferable approach to determine the meaning of prohibited force under international law is to focus on interpreting the UN Charter.

This chapter examines the origin of the customary prohibition of the use of force between States and its relationship to article 2(4) of the UN Charter, focusing on the pre-UN Charter era. In doing so, it critically analyses two possibilities for the norm to have emerged prior to 1945: that it developed prior to the UN Charter and article 2(4) was declaratory of that pre-existing custom, or that article 2(4) crystallised a customary rule that was already in the process of formation. It rejects these two possibilities, arguing that article 2(4) was a significant legal development which went beyond the existing laws of the time in order to found a new international legal order in the aftermath of World War II. Any pre-existing customary limitations on the use of force were significantly broadened by article 2(4), and the drafting process was not accompanied by meaningful State practice developing in parallel with this radical change in the law. Therefore, the customary rule prohibiting recourse to force between States must have arisen after the Charter entered into force. The emergence and development of the customary rule from 1945 onwards are examined in the next chapter.

Chapter 4, ‘Emerging Status as Law? Participation of Indigenous Peoples in International Governance, 2007–2022’, continues the narrative from the point of the adoption of the UNDRIP in September 2007. In this period, the general trend of the proliferation of participatory policies and mechanisms identified in Chapter 3 only intensified. Organizations that had not previously attempted to include Indigenous peoples in a systematic way now adopted mechanisms and policies to do so, while those that had previously instituted such mechanisms or policies sought to enhance them. This chapter maps the contours of this continuing trend, showing how the participation zeitgeist spread through numerous UN organs and international organizations. It assesses the question of states’ and international organizations’ motivations for enabling Indigenous peoples to be heard in such fora. It shows how states and international organizations now increasingly justified participation policies with reference to the UN Declaration on the Rights of Indigenous Peoples. It demonstrates how in nearly all cases barriers to full and effective participation remain.

Chapter 5, ‘New Epoch, Old Stones?’, is the conclusion of the book. It first synthesizes the findings of the examination of practice conducted throughout Chapters 3 and 4, setting out a statement of the scope and content of the emerging rule in (European) international law. Then, by reference to the persistent limitations to participation, it raises questions about what and who the proliferation of mechanisms for Indigenous participation – and the emergence of a legal standard in custom – serves. The chapter engages with the work of Indigenous political theorists to question whether current mechanisms for Indigenous participation in global governance may in part function to legitimize and protect (neo)colonial global economic and political structures. This does not invalidate the conclusion that the right is part of customary international law, nor is it to say that the project of Indigenous peoples’ participation in international governance is not necessarily worth pursuing. Rather, it serves to highlight the limitations of the right, the contingencies of its application, and ultimately to gesture at a space to develop alternative possibilities for Indigenous internationalism and sovereignty.

This chapter introduces the book. It outlines how Indigenous peoples sought, and were denied, membership of the international community in the early twentieth century, contrasting it to the situation that prevails today of Indigenous peoples’ inclusion in international governance. It is therefore timely to take stock of these developments. The introduction situates the book in the field, relating it to scholarship on the law of self-determination and Indigenous peoples’ rights. The key limitations of the book are noted, including those relating to epistemic positionality and representation, and the empirical method employed in the book. Key terms are defined, including ’international governance’ and ’Indigenous peoples’, before the structure of the book is outlined.

Chapter 2, ‘Finding Support for Indigenous Peoples’ Participation in the Sources of International Law’, turns to a doctrinal analysis. It undertakes an examination of relevant sources of international law on self-determination and Indigenous peoples’ rights, in treaties, declarations, and decisions of international judicial and quasi-judicial bodies. We see how the law of self-determination has been interpreted by the latter bodies as meaning – among other things – participation of peoples at the national (but not necessarily the international) level, and how participation is at the heart of the law on self-determination specific to Indigenous peoples. The chapter then turns to customary international law, reviewing and contextualizing various methodologies for its identification and summarizing how the evidence described in later chapters can be interpreted through these methodologies. Through these lenses, I discuss methodological debates, including the legal status we should assign to the UNDRIP in and of itself, how a provision of the UNDRIP might later crystallize into a rule of custom, and how to regard international organizations in relation to the identification of custom.

The author starts by observing that discussions about the foundations and the limits of the powers of international courts, including those of the European Court of Human Rights (hereafter ECtHR), turn around the aims of achieving legal certainty, ensuring legitimacy and justice, and avoiding conflicting obligations which may emanate from different regimes of international law. The chapter reflects on these aims from the perspective of consent as the common basis of the main sources of international law, as listed in Article 38 of the Statute of the International Court of Justice. Proceeding from the case law of the ECtHR, the chapter explores how the recent work of the International Law Commission conceives the role of consent in respect of the main sources of international law, and whether the jurisprudence of the ECtHR remains within the framework of general international law so enunciated.

The author attempts to answer the following question: in an international legal system of which States are no longer the only subjects, what is the role that the consent of IOs plays in the creation of rights and obligations that apply on the international plane? The chapter reflects on the legal agency that IOs enjoy, qua subjects of international law, in the process of formation of general international law and in the acquisition of treaty rights and obligations. In so doing, it advances two claims. The first is that even though IO practice can and should be taken into account in the identification of customary rules, it is not a necessary element in the process of formation of those rules. The second claim of the chapter is that, under current law, IOs can only be bound by treaty rules to which they have consented, which may give rise to problematic gaps between the treaty obligations of IOs and the treaty obligations of their members. In pursuing those claims, the chapter offers some reflections on the systemic and normative implications of the formal involvement of IOs in the making of rules of general and conventional international law.