A wind of change is blowing through the European judicial landscape. During the past decade, the European Union (EU) judiciary has undergone its biggest institutional overhaul in generations, the rise of authoritarian populism in Central and Eastern Europe has prompted a Rule of Law crisis, several supreme and constitutional courts challenged the supremacy of EU law, while the Court of Justice re-articulated the scope of the duty to refer under Article 267 TFEU and, for the first time, found that domestic last-instance courts breaching it triggered state liability. This Article argues that these and similar developments, once looked at together, suggest that something fundamental has shifted in the EU’s judicial architecture. A new form of judicial federalism has emerged, which departs from the traditional way in which relations between EU and Member State courts used to be structured. Although this new federalism is multifaceted and is marked by both centripetal and centrifugal forces, its distinguishing feature is a stronger centralisation, which manifests itself in a considerably expanded federal judiciary, a greater emphasis on hierarchy, a more careful use of European judicial resources, as well as tighter supervision of national procedures and court structures.

This article assesses the implications of national climate litigation for what is termed ‘the international rule of law’. Starting from the finding that the current international climate treaty regime lacks several elements of an international rule of law, such as legal bindingness, clarity, and justiciability, the author explores what national courts contribute to filling these gaps. Deviating from a linear progression narrative, which is prevalent in existing literature, this article provides a more nuanced and complex picture. Whereas successful climate litigation is hardly imaginable without reliance on internationally agreed-upon facts – such as reports by the Intergovernmental Panel on Climate Change and global average temperature levels deemed ‘dangerous’ – doctrinally decisions do not represent a turn toward a stricter rule of international climate law. Instead of applying and progressively developing climate treaties, courts thus far have primarily used these provisions only to develop national constitutional law and regional human rights law. The created system of highly contextual national rule(s) of climate law is a fragmented one which is regionally limited to a few states predominantly located in Western Europe. Consequently, it is a far cry from a truly global rule of international climate law.

The general principle of effective judicial protection grants the right to obtain a remedy in the fields covered by EU law and is an essential component of the EU enforcement toolkit. Recent jurisprudential developments have complexified the role of this principle, by transforming it into a vehicle for the enforcement of the rule of law in the EU. As a result, the principle of effective judicial protection appears as the factotum of the EU legal system: it acts as a fundamental right and is an expression of the EU rule of law; furthermore, it is a legal basis to influence national fundamental rights and to impose procedural obligations on the EU institutions. This overview Article offers a novel account of the evolution of this principle in the EU legal landscape. First, it reflects on the trajectory of this evolving principle in the EU case law and in the academic discourse. Second, it identifies conceptual issues surrounding the role of effective judicial protection in the EU legal order in the light of the latest jurisprudential developments.

The interaction between immunities and jurisdiction is complex. One lacuna is whether the international legal principle of state immunity is a rule or principle in its own right or an exception to a pre-existing jurisdiction. In the context of international arbitration disputes, this distinction is significant. States have been relying on immunity to exclude the jurisdiction of national courts to support the international arbitral process. This Article argues there is now a growing set of common and consistent practice according to which state immunity operates as a rule or principle lex specialis to a more general set of rules or principles governing the enforcement jurisdiction of national courts.

Since the adoption of the first United Nations Security Council (UNSC) counterterrorism resolution after the 9/11 attacks, the UNSC has increasingly required the domestic criminalization of “terrorism” acts and ancillary activities. Without the inclusion of an explicit international humanitarian law (IHL) or humanitarian exception, the UNSC has – so far – failed to harmonize the counterterrorism legal framework with IHL, leaving it up to States to define the interaction between the two. In their national legislation and courts, States’ interpretations have varied but counterterrorism legislations have been used to adjudicate conducts in armed conflicts, regardless of their legality under IHL. As the domestication of UNSC offences is ongoing, good practices are highlighted in this paper and recommendations are offered to ensure the development of international customary law in accordance with IHL.

This Article aims to examine the social media jurisprudence of national courts in a selected set of EU Member States by focusing on judicial dialogue specifically via references to the case law of other courts. Do judges in social media cases engage with the case law of peers, and if so how and to what extent? The analysis investigates whether national judges draw on the jurisprudence of higher domestic courts, foreign courts and/or European supranational courts—the Court of Justice of the European Union (CJEU) and the European Court of Human Rights (ECtHR)—and explores the use of such jurisprudence. It is based on 147 cases from the constitutional and/or supreme courts of Bulgaria, Croatia, Greece, Italy, Latvia, Slovakia, and Slovenia. Although judicial dialogue is generally limited in the cases under study, the analysis illustrates the different ways in which courts interact with the rulings of peers and informs on the latter’s contribution to judicial assessment.

Domestic climate change litigation is prospering across the globe to the extent of becoming a transnational phenomenon of growing importance. At the international level the Paris Agreement, although still in its infancy, has been established as the core element of the climate change governance framework. This article explores the still opaque relationship between domestic climate change litigation and the Paris Agreement. It is argued that dynamic interaction between domestic litigation and the Paris Agreement may improve the overall efficacy of both regimes. On the one hand, an examination of the Paris Agreement's architecture and provisions reveals pathways that are already being used or can be explored further in litigation. On the other hand, litigation can assist and complement the Paris Agreement with regard to its implementation and progress towards its overall goals. The result may deliver more than a multi-level perspective on climate change law. As it captures the law in action on different levels, the proposed ‘cross-level’ approach has due regard to the implications of the mutual supportiveness or complementarity of legal tools. It also thereby responds to the concern of whether the law can be of significant benefit in addressing complex global issues like climate change.

This introductory paper to the symposium hosted by the Leiden Journal of International Law, and edited by the authors, deals with the function of domestic courts as agents for the development of international law. The paper ‘sets the scene’ for the contributions to the symposium, which seek to trace the impact of domestic courts in the development of canonical areas of international law, such as jurisdiction, immunity, state responsibility, the law of international organizations/human rights, and the law of armed conflict/conduct of hostilities. It discusses the formal quality and actual influence of domestic-court decisions on the development of international-law, and introduces the concept of ‘agents’ of international-law development. This is the analytical perspective that the contributions to the symposium adopt.

This article examines the extent to which state officials are shielded from foreign jurisdiction by functional immunity when they stand accused of committing international crimes. It argues that the development of the principle of individual responsibility for international crimes should be understood as posing a limit to the operation of the rule of functional immunity. States have agreed that international crimes, even when committed within the context of the ostensible exercise of state authority under international law, do not qualify as official acts for functional immunity purposes since they can no longer be solely attributed to the state and not to the official personally. The article thereby takes issue with the increasingly popular conceptualization of functional immunity in terms of an act of state immunity, in which attribution, rather than exclusive attribution, is the controlling notion. It does acknowledge that international law may pose limits on the competence of national courts to establish jurisdiction in certain circumstances, but proposes to undo the discussion of the shackles of immunity law and to recognize the operation of an alternative, less far-reaching legal principle.

On 26 November 2008 the Czech Constitutional Court (hereinafter Court) handed down a long-awaited opinion in which it unanimously found the Lisbon Treaty (hereinafter Treaty) to be compatible with the Czech constitutional order. The decision has drawn broad attention at all levels, be it political circles, academia or even general public. It is certainly one of the most significant decisions in the Court's history and it has EU-wide implications.