Membership is central to the EU, as it is to any other international organisation. Withdrawal has assumed centre-stage through Brexit. While there is literature that is relevant to membership, most notably through academic discourse on differentiated integration, there is little more general inquiry concerning membership, the concept of which has importance and implications over and beyond more particular avenues of scholarship. This article examines the formal and substantive dimensions of membership and withdrawal in the EU.

After the financial crisis of 2008, the European Union (‘EU’) not only increased its substantial legislation regarding financial services, but also built up a strong and unified system of financial market supervision. In particular, central surveillance authorities were created. These were given far-reaching competences with regard to substituting dysfunctional national authorities or players in the financial services sector. The three European Economic Area (‘EEA’) and European Free Trade Association (‘EFTA’) States—Iceland, Liechtenstein, and Norway—participate in the EU's internal market through their membership of the EEA. In order to continue participating on an equal footing in the internal market for financial services and to honour their duty to maintain homogeneity, the EEA EFTA States also had to incorporate the new institutional setup regarding financial services supervision. This obligation, however, in particular relating to certain intrusive powers of the new surveillance authorities, collided with some constitutional reservations, above all of the two Nordic EEA EFTA States. This article will show how these conflicting aims could be merged into a system that on the one hand guarantees the unified overall approach needed for strengthened surveillance of the internal market for financial services, and on the other hand safeguards certain constitutional reservations of the EEA EFTA States. It also looks at how third countries that do not (fully) participate in the internal market, such as the United Kingdom and Switzerland, are likely to be treated in this context by the EU.

This article argues that constitutional pluralism is not a theory merely for times of equanimity, but crucially, in times of constitutional conflict. Given that it rests on the premise of regarding law as a dynamic, incrementally developing creature, constitutional conflict is no exceptional event, and represents an important element of the system's functioning. However, this does not mean that every point of conflict necessarily means progress for the pluralist system as a whole: it is possible to distinguish constructive from destructive conflict. In this respect, this piece will put forward a normative argument concerning the limits to which the auto-correct function of constitutional pluralism can stretch. In so doing, this piece will look at the recent jurisprudence of constitutional conflict at the EU and national level to demonstrate the limits of constructive conflict, as well as show how the example of Poland falls into the category of destructive conflict.

This Article argues that the cooperation obligations of the Member States under EU law are best understood as forming part of an overall duty of EU loyalty and elaborates on the consequences of framing it in this way. EU loyalty legally requires Member States to make the common EU interest their own. The Article further demonstrates that EU loyalty is more relevant and more stringently applied in EU external relations than within the EU legal order. Loyalty obligations of the Member States reach into the future, extend to hypothetical situations, and are at a comparatively high level of abstraction aimed to protect the Union's ability to act effectively on the international plane. This limits Member States’ margin of manoeuvre, including when they take unilateral external action within the realm of their retained national competences. The Article explains that this may be functionally justified by the high stakes of non-concerted external action. However, and in particular with the EU's increased external powers and the ever-growing relevance of international cooperation, the stringent application of cooperation requirements should be (better) explicated and justified.

In April 2019, the Court of Justice of the EU (‘CJEU’) handed down its Opinion (C-1/17) on the compatibility of the Investment Court System (‘ICS’), that is the Investor-State Dispute Settlement (‘ISDS’) mechanism under the EU-Canada Comprehensive and Economic Trade Agreement (‘CETA’), with EU law. This article puts Opinion 1/17 in its broader (policy and legal) context, focusing on the salient issue of compatibility with the principle of autonomy of the EU legal order. It argues that the Court's openness to this judicial competitor was an acknowledgment of the need to maintain the powers of the Union in international relations. However, Opinion 1/17 should not be perceived as an automatic green light for any future investment court (such as the Multilateral Investment Court) as the autonomy test it introduces is a rather difficult one to pass.

EU Internal Market law and international arbitration increasingly interact with each other but there are important areas of conflict between the two that represent an obstacle to market integration in a common area of justice. The article examines, from the perspective of EU public economic law, these areas of conflict to assess the extent to which the Internal Market needs harmonised rules on commercial arbitration to support dispute resolution and access to an efficient delivery of justice within its operation. The current state of affairs is unsatisfactory and it lacks legal certainty. If properly regulated, commercial arbitration can become an important instrument functional to EU market efficiency.

The lack of clarity as to the scope of the health insurance exception enshrined in Article 206 of the Solvency II Directive has created uncertainties surrounding the implications for government intervention in the private health insurance market. A contentious interpretation of the health insurance exception, offered by former EU Commissioner Bolkestein, and the approach subsequently taken by the Commission and the Court of Justice of the European Union in assessing the compatibility of Member State intervention in private health insurance have led to a divergence in the application of EU law, which further increases uncertainties around the legality of Member State intervention. This article proposes an alternative interpretation of the health insurance exception that draws on a contemporary understanding of private health insurance as a socio-economic institution aimed at achieving a highly competitive social market economy. This alternative interpretation extends the applicability of the health insurance exception from substitutive private health insurance to complementary private health insurance that covers statutory user charges and thus improves the compliance of national health insurance systems in several Member States with EU law and enhances the coherence of EU law.

This article reviews the legal and political science literatures on the extensive interpretation of the European fundamental freedoms and on possible ways out. The common market rules were originally laid down in an international treaty, the Treaty of Rome. In functional terms, this treaty became a de facto constitution, implying that its content, including the fundamental freedoms, were constitutionalised. We review how this constitutionalisation constrains legislators at the Member State and European levels. In order to identify possible ways out, we also review several reform options: institutional reforms of the European judicial system; the de-constitutionalisation of the fundamental freedoms; counterbalancing these freedoms with further strengthened social rights; and contestation of over-constitutionalisation within the given primary law framework. We conclude that reform options are available that could gradually free the legislators from the over-constitutionalisation of the common market rules. Such options should become part of the ‘Conference on the Future of Europe’ process and debates about EU reforms in general, as more flexibility is warranted in a heterogeneous EU.

This article analyses the main debates over the application of the Charter to disputes between private parties and assesses the ways in which the case law over the last ten years has responded to them. The article goes on to propose an alternative schema, whereby horizontality can be understood as a structural principle of EU fundamental rights adjudication on its own terms, rather than as an extension of the direct effect doctrine. It is argued that a self-standing principle of horizontality with equally valuable—yet operationally distinct—direct, indirect, and state-mediated manifestations, could respond more coherently to the conceptual, procedural, and remedial challenges displayed in the case law.

Article 6 Treaty on European Union sets out two sources of fundamental rights in the EU—the Charter and the general principles of EU law—without specifying a hierarchy between them. Even though the Charter became binding over a decade ago, the Court of Justice of the European Union (‘CJEU’) is yet to clarify unequivocally how these two sources interact. In this article I argue based upon the relevant legal framework that the Charter ought to replace the general principles it enshrines. This leaves a role for general principles in the incorporation of new and additional rights into the EU legal framework. Such an approach is necessary to ensure that the Charter achieves its aims in enhancing the visibility of the rights protected by EU law, while also providing the impetus for more coherent rights protection within the EU. What an extensive survey of CJEU case law in the field of non-discrimination shows, however, is that the CJEU has struggled to let its general principles case law go, potentially hampering the transformative potential of the Charter.

The binding legal force that the Charter acquired with the Treaty of Lisbon has led some national constitutional courts to adopt an entirely new approach to EU fundamental rights. Most notably, the Austrian Constitutional Court, the Italian Constitutional Court, and the German Federal Constitutional Court have explicitly made the Charter a yardstick of constitutional review. This article compares and contrasts the approaches of these three courts to the Charter. It shows that the strategies of the Austrian and German Constitutional Courts have many characteristics in common, including that national constitutional rights are treated as a primary source and the Charter as a mere secondary benchmark in the majority of cases. The most distinctive feature of the Italian Constitutional Court's strategy is that it mainly aims to prevent ordinary courts from circumventing constitutionality refences by directly applying the Charter. The article concludes by arguing that it has many advantages when national constitutional courts adopt the Charter as a yardstick of constitutional review. It is for the constitutional courts and the CJEU to ensure that these benefits are not outweighed by some serious drawbacks of constitutional review in light of the Charter.

This contribution will tackle a central question for the architecture of fundamental rights protection in the EU: can we envision a Charter that fully applies to the Member States, even beyond the limits of its scope of application? To improve our understanding of the boundaries of the Charter and the potential for further expansion, I will examine the legal avenues through which the CJEU has extended the scope of application of EU fundamental rights in fields of state powers. While the latent pull of citizenship towards a more expansive application of the Charter has not been fully realized, the principle of effective judicial protection (Article 19(1) TEU) has recently shown potential for protection under EU law beyond the boundaries of the Charter. As will be argued, effective judicial protection may well become a doorway for full application of the Charter to the Member States. While such an outcome might currently seem politically unsound, I contend that a progressive case-by-case expansion of the applicability of the Charter to the Member States would be welcome from the standpoint of a robust notion of the rule of law in the EU.