EU Citizenship: A Constitutional Law Perspective on the Activist Case Law of the Court of Justice of the European Union

Abstract

The institution of citizenship of the European Union (EU) is one of the key milestones of European integration. However, it is linked to the nationality of a Member State because, under the Treaties, only persons holding the nationality of a Member State are citizens of the Union. This poses a significant challenge for future integration, as it requires developing a coherent approach to citizenship issues. Thus, EU citizenship raises questions in the context of multilevel constitutionalism: whilst the rules governing the acquisition and loss of nationality remain within the discretionary powers of the Member States, these rules strongly influence EU citizenship and the rights associated with this status. In line with these findings, it is also worth noting the case law of the Court of Justice of the European Union (CJEU), which can be considered particularly proactive and activist in its approach. In the present contribution, we aim to focus primarily on the relationship between EU citizenship and nationality. To this end, two recent CJEU cases will be presented (both concerning the loss of EU citizenship). Although the factual backgrounds of the two cases differ, we believe that reviewing these judgments together is the best way to highlight the specific features of the constitutional-law approach to EU citizenship and the consequences of the activist case law of the CJEU.