Primacy of European Union law

The principle was derived from an interpretation of the European Court of Justice, which ruled that European law has priority over any contravening national law, including the constitution of a member state itself.^[2][3][4] For the European Court of Justice, national courts and public officials must disapply a national norm that they consider not to be compliant with the EU law.


The majority of national courts have generally recognized and accepted this principle, except for the part where European law outranks a member state's constitution. As a result, national constitutional courts have also reserved the right to review the conformity of EU law with national constitutional law.^[5]


Some countries provide that if national and EU law contradict, courts and public officials are required to suspend the application of the national law, bring the question to the national constitutional court and wait until its decision is made. If the norm has been declared to be constitutional, they are automatically obliged to apply the national law. This can create a contradiction between the national constitutional court and the European Court of Justice, like on 7 October 2021 when the Polish Constitutional Tribunal issued a judgment in case K 3/21 challenging the primacy of EU law in certain areas of the Polish legal order.^[6]

In Costa v. ENEL.^[7] Mr Costa was an Italian citizen opposed to the nationalisation of energy companies. Because he had shares in a private corporation subsumed by the nationalised company, ENEL, he refused to pay his electricity bill in protest. In the subsequent suit brought to Italian courts by ENEL, he argued that nationalisation infringed EU law on the state distorting the market.^[8] The Italian government believed that not to be an issue that even could be complained about by a private individual since it was a decision to make by a national law. The ECJ ruled in favour of the government because the relevant treaty rule on an undistorted market was one on which the Commission alone could challenge the Italian government. As an individual, Mr Costa had no standing to challenge the decision, because that treaty provision had no direct effect.^[9] But on the prior issue of Mr Costa's ability to raise a point of EU law against a national government in legal proceedings before the courts in that member state the ECJ disagreed with the Italian government. It ruled that EU law would not be effective if Mr Costa could not challenge national law on the basis of its alleged incompatibility with EU law.


In other cases, state legislatures write the precedence of EU law into their constitutions. For example, the Constitution of Ireland contains this clause: "No provision of this Constitution invalidates laws enacted, acts done or measures adopted by the State which are necessitated by the obligations of membership of the European Union or of the Communities".


Article I-6 of the European Constitution stated: "The Constitution and law adopted by the institutions of the Union in exercising competences conferred on it shall have primacy over the law of the Member States". The proposed constitution was never ratified, after being rejected in referendums in France and the Netherlands in 2005. Its replacement, the Treaty of Lisbon, did not include the article on primacy but instead included the following declaration: