What is the European Court of Justice?

Formally known as the Court of Justice of the European Union (CJEU), the ECJ is the judicial authority of the EU, ruling on member states’ compliance with EU treaties, interpreting EU law and deciding on the legality of EU institutions’ actions. The court is divided into two: the Court of Justice and the General Court. The Court of justice has one judge from each Member State.

There are also 9 Advocates General who are drawn from a range of states. The General Court has two judges from each state. While the UK remains a member of the EU, the UK Supreme Court must refer questions to the ECJ on the interpretation of the EU treaty and secondary legislation; all other courts have a discretion as to whether to refer such cases. All courts must refer cases on the validity of the actions of EU institutions.

Find out more – read our fact profile on the differences between the European Convention on Human Rights, the European Court of Human Rights and the European Court of Justice or read our explainer on the Court of Justice of the European Union.

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