Since the establishment of the Court of Justice of the European Union in 1952, its mission has been to ensure that "the law is observed" "in the interpretation and application" of the Treaties.
As part of that mission, the Court of Justice of the European Union:
The Court thus constitutes the judicial authority of the European Union and, in cooperation with the courts and tribunals of the Member States, it ensures the uniform application and interpretation of EU law.
As each Member State has its own language and specific legal system, the Court of Justice of the European Union is a multilingual institution. Its language arrangements have no equivalent in any other court in the world, since each of the official languages of the European Union can be the language of a case. The Court is required to observe the principle of multilingualism in full, because of the need to communicate with the parties in the language of the proceedings and to ensure that its case-law is disseminated throughout the Member States.