Costa v ENEL [1964]

Flaminio Costa v ENEL Case 6/64 was a landmark ruling by the European Court of Justice (ECJ) in 1964. It established the principle of the supremacy of EU law over national law in EU member states.

In the case, Flaminio Costa, an Italian citizen, challenged a decision by the Italian national electricity company, ENEL, to increase its prices. Costa argued that the increase violated the Treaty of Rome, which established the European Economic Community (EEC) and prohibited member states from imposing measures that would restrict the free movement of goods and services.

The Italian courts dismissed Costa's case, arguing that national law took precedence over EU law. Costa appealed the decision to the ECJ, which ruled that EU law has direct effect and takes precedence over national law. The Court held that the EEC Treaty was not only a treaty between member states but also created a new legal order that was independent of the national legal orders of the member states. Therefore, member states were obliged to apply EU law and ensure that it takes precedence over any conflicting national law.

The Costa v ENEL ruling established the principle of the supremacy of EU law, which has since become a fundamental principle of EU law. The ruling means that EU law has direct effect and must be applied by the national courts of member states, even if it conflicts with national law. This ensures the uniform application and interpretation of EU law across all member states and prevents member states from adopting laws that conflict with EU law.
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