History and Theory: Towards a New History of European Law

It was a turning point in the history of European integration and a unique moment for the first President of the European Commission, Walter Hallstein. On 16 June 1965 in the afternoon, Hallstein appeared before the European Parliament (EP) to express his strong support for the constitutional interpretation of European law launched by the European Court of Justice (ECJ) in the new Van Gend en Loos (1963) and Costa v ENEL (1964) judgments. Here the ECJ had controversially assumed the competence to define the relationship between European law and national constitutional orders. By doing so the ECJ sidestepped the respective constitutional clauses of the member states on how to receive international (and European) law. Primary legal norms from the founding treaties, when clear and unambiguous, would have direct effect inside the legal order of the member states as well as primacy vis-à-vis national legislation, whether precedent or antecedent. This was a remarkable breakthrough for a constitutional interpretation of European law.