Integration Responsibility: The Relationship of National Constitutional Courts to the Court of Justice of the European Union

Hierarchy or Collegiality?

Abstract

As long as the peoples of Europe are unable to create a homogeneous, united society, the principle of ‘unity in diversity’ will be a natural limit to the development of the ‘ever closer union’ clause, and this is not a mere philosophical or theoretical argument; it is rather a fact-based inadequacy that must be reflected in the European legal order and the concrete competences and their limits, especially in the relationship between the Court of Justice of the European Union and the European national constitutional and higher courts. The undefined nature of the relationship between European Union (EU) law and national constitutions (resulting from the supranational nature of integration) forced European national constitutional courts to assume a role that could also be seen as a functional change in terms of the entirety of the European constitutional judiciary. The role of these bodies seems to be complemented by a kind of ‘integrational’ function; the European national constitutional courts must no longer only defend their national constitutions but must do so while considering the proper advancement of the integration process. They must act in a manner that upholds the Court of Justice of the European Union’s (CJEU) right to an authentic interpretation of the Treaties; however, taking into account that the CJEU, as an institution of the EU, is not entitled to make decisions ultra vires against the framework set by the Treaties.