The primacy of the rule of law and member states’ constitutional identities

This essay discusses the phenomenon of both divergence and convergence in understanding the ‘rule of law’ by EU member states and EU institutions respectively. The potential for constitutional conflict can normatively be located in the relation between articles 2 (on the common foundational values of member states and EU) and 4(2) (on the duty to respect the constitutional identity of member states) of the TEU. The structural nature of the potential for constitutional conflict is explained by the ‘juridictional gap’ between member state courts and the European Court of Justice. By now, however, on the part of national courts which allow for ultra vires or constitutional identity review (like the French and Portuguese) techniques have been developed to reduce the scope for conflict by focussing on convergence of rule of law understandings. These do neither fully reduce the ‘jurisdictional gap’ nor the diversity of authentic (non-abusive) understandings of the rule of law which may be reflected in differences in the constitutional identity of member states. In particular, the revival of a strictly formal and hierarchical understanding of an absolute doctrine of primacy in the case of the Court of Justice which is based on a ‘thin’ concept of the rule of law that outflanks ‘thicker’ concepts obstructs possibilities for resolving constitutional conflict. For resolution of such conflicts, however, it is unavoidable to understand the doctrine of primacy as subject to a ‘thick rule of law’ conditionality, which seems occasionally to be implied in the ECJ’s case law, but is too often missing.