Considering that judicial fragmentation and convergence concern the interpretation of human rights norms and provisions, this chapter discusses how the human rights bodies under analysis engage with the theory of treaty interpretation. In particular, the chapter illustrates how the human rights systems are engaging differently with judicial dialogue. Through a detailed analysis of the practice of each body, this chapter shows how judicial dialogue led to convergence and how the lack of it led to fragmentation. However, the chapter also highlights situations where despite judicial dialogue fragmentation still arose, discussing the duality and complexity of this instrument for the maintenance of convergence.

This chapter focuses on the distribution of the burdens of argumentation in proportionality analysis. A survey of rights adjudication in Latin America and other countries suggests that the idea of proportionality as an interchange of reasons and justifications has substantial conceptual and institutional indeterminacies, which may only be solved with a view on the normative consequences of the different options in different contexts. The chapter explores two extreme versions of the distribution – the dialogic and the unilateral – but also the gradation or continuum between them, with flexible and strict versions of dialogue and open and closed modalities of unilateralism. The selection of one or another point along the spectrum has consequences in terms of normative rationales such as democracy, epistemic quality, integrity, equality or legal security, and should carefully account for contextual elements like patterns of access to justice, legal culture and procedural architectures.

The law of the sea is a great laboratory for observing the fabric of international law through the interactions between a variety of judicial bodies with jurisdiction to interpret and apply the same legal rules and principles. At first, the plurality of judicial fora available under UNCLOS has created concerns of fragmentation and of competition and forum shopping. These have proved so far unwarranted, since the tribunals generally deliver a uniform interpretation of the applicable law or tend at least toward harmonization. Tribunals have aimed to achieve clarity and consistency of the case law as well as transparency and predictability of the delimitation process. The concept of acquis judiciaire has been used to designate this mechanism of gradual building of a uniform law through the reiteration and cross-referral to existing judicial decisions. It is both a concept and a regulatory tool. It underlies a wilful search of harmonization and shows that judges are essential actors for ensuring the coherence of the international legal system.

This introduction reviews scholarship on international legal fragmentation, lays out a framework for understanding international judicial cross-fertilization, and previews the contributions and their findings. Existing scholarship on international legal fragmentation, we argue, has moved through three phases over the past several decades. In the first, legal scholars and practitioners reacted with alarm to the judicial proliferation of the post–Cold War years, which they feared would create overlapping jurisdiction and conflicting interpretations of law. Following this period, the new century saw the pendulum swing toward a second, more optimistic picture in which international courts addressed fragmentation through “management” techniques, producing unity in international law. We can detect the opening salvos of a third wave, as skeptics have questioned the management account, pointing to the mixed motives of international judges and the limits of cross-fertilization. In this volume, we build on the existing literature by theorizing the actors of cross-fertilization and their motives, and by distinguishing between procedural and substantive cross-fertilization.

Chapter 2 sets the descriptive, theoretical, and methodological stage for revisiting the behavior of national courts in the process of European integration. It describes the central institutional mechanism through which national courts can partner with the European Court of Justice (ECJ) to apply European law, exercise de facto judicial review, and promote integration: the “preliminary reference procedure.” It summarizes how national courts’ use of this procedure has been theorized by the prevailing account of the judicial construction of Europe: the “judicial empowerment thesis.” And it highlights suggestive qualitative and quantitative evidence that this thesis may conceal as much as it reveals. The chapter concludes by outlining the fieldwork strategy deployed to revisit the judicial empowerment thesis in Chapters 3 and 4 and probe whether national judges have harbored more diffuse and persistent resistances to European law, the ECJ, and institutional change than has hitherto been acknowledged.

National judicial systems within the European Union (EU) face pressures toward alignment under the policy agendas for judicial cooperation connected with the Lisbon Treaty and the widespread practice of ‘transnational borrowing’ among courts. Using the CJEU and ECtHR as case studies in the phenomena of judicial culture and transnational judicial communication, this chapter explores how constitutional norms and formal policies interact with contextual influences (including informal judicial interaction and evolving national ideas and practices regarding judging and judicial organisation) to produce increasing legal alignment among the member states. In doing so, the chapter explicitly highlights the need to combine comparative legal analysis with socio-legal research methods in order to understand the evolution of constitutional law.

The conclusion summarizes the supranational aspects of the ECHR and reflects on the wider narrative of supranationalization of the ECHR, including its driving factors and countertrends. It further demonstrates that growing resistance towards the ECtHR, as far as it goes beyond system inherent criticism, may partly be the result of increased openness and integration in the first place and could in fact lead to a refinement of Convention law. The ECHR’s supranational aspects also lend themselves to a communitarian perspective. The conclusion therefore argues that the findings of the study allow to give meaning to the notion of Convention community which is characterized by Convention rights as community interest norms, for the protection of which the ECtHR enjoys an inalienable core of autonomy, membership of domestic authorities and natural and legal persons as well as subsidiarity and moderated supremacy of Convention law as ordering principles.

The EU fundamental right to asylum, enshrined in Article 18 of the Charter, has always been a subject of scholarly debate. While some scholars have interpreted Article 18 as limited to a right to seek asylum, others have argued that it also confers an individual right to be granted asylum under certain conditions. Clarifying the scope and effects of the EU fundamental right to asylum is no longer of purely academic interest; courts across the EU are increasingly faced with complaints regarding its violation following the EU’s and Member States’ policy responses to the 2015 refugee crisis. The debate has been fuelled by the broad wording of the EU fundamental right to asylum, defined in relation to the rules of the Refugee Convention and EU Treaties. This chapter considers the scope of Article 18 of the Charter compared to the principle of non-refoulement guaranteed by the 1951 Refugee Convention; the extraterritorial application of the EU fundamental right to asylum and its content; and the main actors contributing to the normative clarification of the right to asylum. The chapter demonstrates the added value of the EU fundamental right to asylum as reflected in its various functions at EU and national levels.

Chapter 4 replies to the argument that international courts who decide important policy decisions take them off the public agenda and therefore stifle public debate. The chapter explains that an international judgment is often just the entry point into a public discussion and a dialogue with the relevant authorities. In fact, the ensuing public deliberation may be superior to what would happen absent international courts' intervention. International courts shift the discussion from interests and naked power to rights, and they change the social settings in a way that processes and disseminates information well to wider segments of the public. International courts create friction with the executive, guide the legislator, and can help the national judiciary, all leading to a more vibrant debate. Finally, international courts provide numerous lawyers with vital training that they can use to better the public discourse.

The concept of constitutional identity (Verfassungsidentität) has been unfolded by the German Federal Constitutional Court (GFCC) to frame and control the process of European integration. Jurisprudence ranging from the renowned Solange to the famous Lissabon judgments has never been undisputed. Although not found in the wording of the German Basic Law, constitutional identity is nowadays mainly associated with the Basic Law’s Art. 79(3). Accordingly, the notion primarily comprises the protection of human dignity, the principle of democracy, the social state objective, and the rule of law. The GFCC exercises its control by a fundamental rights review, the ultra vires review, and the constitutional identity review. All three types lately seem to have been merged under the umbrella of constitutional identity review. Meanwhile, the concept of Integrationsverantwortung‘ (responsibility for integration) requires all German constitutional bodies to respect the European integration agenda and to protect German constitutional identity. Arts. 4(2) and (3) TEU underpin the necessity of close and constructive judicial dialogue between the ECJ and the national constitutional courts.