Costa v Enel [1964] ECR 585

Eu, EU Law, European Union Law, Costa, Enel

Costa v Enel [1964] ECR 585 is a European Union Law case concerning Supremacy of EU Law.


Costa v Enel involved an alleged conflict between a number of Treaty provisions and an Italian statute nationalising an electricity company.

The law enacted by Italy to nationalise its electricity industry was incompatible with certain provisions of what is now the Treaty on Functioning of the European Union (TFEU). 

Moreover, the claimant argued that this violated the Italian Constitution (1962) as well as EU Law on distortion of the market (1958). In the Italian Constitution, it states that the Italian courts give precedence to what is mist recent, in Costa v Enel, the Italian Law was most recent. 


Could national law enacted after Italy’s accession to the union prevail over EU law?


In conclusion, the EU said that they ‘must allow Supremacy of EU Law over national law in order to encourage effectiveness of EU Law generally.’

Furthermore, the Court of Justice of the European Union held that it was not legally possible for member states to derogate from EU law by enacting conflicting domestic provisions because “the member-states, albeit within limited spheres, have restricted their sovereign rights and created a body of law applicable both to their nationals and to themselves”.

The CJEU remarked that if the strength of EU law is weakened by giving favour to contravening internal law, the aims of the European Union will not be achieved. 

Judgement extract:

“The integration into the laws of each Member State of provisions which derive from the Community, and more generally the terms and the spirit of the Treaty, make it impossible for the States, as a corollary, to accord precedence to a unilateral and subsequent measure over a legal system accepted by the on a basis of reciprocity. Such a measure cannot therefore be inconsistent with that legal system. The executive force of community law cannot vary from one State to another in deference to subsequent domestic laws, without jeopardizing the attainment of the objectives of the Treaty. The laws stemming from the Treaty, an independent source of law, could not, because of its special and original nature, be overridden by domestic legal provisions, however framed, without being deprived of its character as Community law, and without the legal basis of the Community itself being called into question”.


C-6/64, (1964) CMLR 425, [1964] ECR 585, R-6/64, [1964] EUECJ R-6/64, [1964] EUECJ C-6/64

Read our notes and our cases on Supremacy of EU Law for more information.