Sole Architect? How the CJEU Reinvented Europe’s Constitution

Abstract The principle of autonomy, initially conceived by the Court of Justice of the European Union (CJEU) to safeguard the independence of the nascent Community legal order, has mutated into a potent doctrine of judicial hierarchization. While the EU Treaties remain silent on the specific hierarchical relationship between Union and national law, the Court has decisively filled this constitutional void. It asserts that EU law constitutes a ‘new legal order’ stemming from an autonomous source, distinct from and independent of the constitutional laws of the Member States. As the Court emphasized in its CETA opinion, this autonomy is rooted in a ‘structured network of principles, rules and legal relations’, a concept the CJEU now positions as the necessary foundation for its doctrine of absolute primacy. This essay argues that the CJEU has operationalized this conceptual link between autonomy and primacy to unilaterally reconstruct the European constitution, effectively transforming a system of cooperative federalism into a quasi-federal hierarchy with the Court itself positioned as the ultimate arbiter. The following analysis traces this judicial reinvention through seven distinct stages. First, it contrasts the CJEU’s claim of autonomous validity with the prevailing view of national constitutional courts, which ground the authority of EU law in domestic ‘application commands’ bounded by national constitutional identity. Second, it exposes the doctrinal fragility of the autonomy concept, arguing that it rests on circular reasoning and lacks the democratic legitimation of a true ‘constitutional moment’. Third, it proposes an alternative ‘Treaty Model’ based on the text of Articles 4(2) and 5(2) TEU, conceptualizing the EU as a compound of interlinked sub-orders rather than a free-floating autonomous entity. The subsequent sections detail how the Court has utilized autonomy to enforce absolute primacy (Fourth Stage) and to homogenize national legal systems through a rigorous ‘values jurisprudence’ based on Article 2 TEU (Fifth Stage). Finally, the essay examines the institutional consequences of this doctrine: the Court’s claim to exclusive Kompetenz-Kompetenz (Sixth Stage) and its establishment of a supranational oversight mechanism over national judiciaries (Seventh Stage), effectively bypassing national constitutional courts. The essay concludes that while the CJEU has acted as the ‘sole architect’ of this transformation, its construct of a quasi-federal hierarchy remains doctrinally unsustainable, as it fundamentally conflicts with the derivative nature of the Union’s authority and the constitutional reality of the Member States.