C-6/64 Flaminio Costa v ENEL [1964]

C-6/64 Flaminio Costa v ENEL [1964] ECR 585 is a pivotal decision by the European Court of Justice (ECJ), playing a crucial role in solidifying the principle of the primacy of European Union law over the laws of its member states. This landmark case set a precedent that has been fundamental in shaping the legal landscape of the European Union.

Flaminio Costa, a Milanese lawyer and shareholder of Edisonvolta, opposed the nationalisation of the Italian electricity sector by the government. When ENEL, the state-owned electricity company, sent him a bill, Costa refused to pay, arguing that the nationalisation law violated both the Italian Constitution and the EEC Treaty. The Italian Constitutional Court ruled that the Treaty of Rome could not prevail over the nationalisation law. In a separate case, another judge referred the matter to both the Italian Constitutional Court and the European Court of Justice (ECJ).

The ECJ dismissed the Italian government's claim of inadmissibility, asserting its authority to provide an authoritative interpretation of the EEC Treaty. The judgment emphasised the unique nature of the EEC Treaty, creating a legal order binding member states and individuals. The ECJ stated that EU law, as an independent source, could not be overridden by domestic laws without jeopardising the legal basis of the Community.

The key passage highlighted the incompatibility of domestic laws with the special and original nature of EU law: "It follows... that the law 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".

On the merits, the ECJ found that the EEC Treaty provisions on competition and State aids had no direct effect, meaning individuals could not invoke them in challenging national laws. The interpretation of the right of establishment was narrow, suggesting consistency with the nationalisation law if non-discriminatory. The ECJ left it to the referring court to determine the compatibility of the nationalisation law with the EEC Treaty's provisions on commercial monopolies.

Flaminio Costa v ENEL is a landmark case that established the primacy of EU law over national laws. The judgment emphasised that EU law is an independent source, binding member states and individuals, and cannot be overridden by domestic legal provisions. This principle of supremacy has been fundamental in shaping the legal framework of the European Union. While Article I-6 of the proposed European Constitution and the Treaty of Lisbon did not explicitly include the article on primacy, a declaration was added, recalling the Costa v ENEL judgment. The case marked a significant step in defining the legal relationship between EU law and national laws, ensuring the effectiveness of EU law across member states.
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