European Court of Justice, judicial branch of the European Union European Community (EC), an economic and political confederation of European nations, and other organizations (with the same member nations) that are responsible for a common foreign and security policy and for cooperation on justice and home affairs.
..... Click the link for more information. (EU). Located in Luxembourg, it was founded in 1958 as the joint court for the three treaty organizations that were consolidated into the European Community (the predecessor of the EU) in 1967. By the early 1990s, the court was composed of 9 advocates general and 15 judges—one judge from each of the EU nations. All members of the court are appointed for renewable six-year terms by agreement among the EU nations.

The court interprets EU treaties and legislation. Although it may attempt to reconcile differences between national and EU laws, ultimately its decisions overrule those of national courts; they have tended to expand the EU's domain. Increased litigation over the years led to the establishment (1988) of a lower court, the Court of First Instances; appeals to the Court of Justice are tightly restricted. International law cases involving nations outside the EU are heard by the World Court in The Hague; the European Court of Human Rights in Strasbourg, France, is recognized by the members of the Council of Europe Council of Europe, international organization founded in 1949 to promote greater unity within Europe and to safeguard its political and cultural heritage by promoting human rights and democracy. The council is headquartered in Strasbourg, France.
..... Click the link for more information. and hears cases relating to the European Convention for the Protection of Human Rights and Personal Freedoms.

European Court of Justice

Judicial branch of the European Union (EU), established in 1958 to ensure the observance of international agreements negotiated by predecessor organizations of the EU. Headquartered in Luxembourg, it reviews the legality of the acts of EU executive bodies and rules on cases of civil law between member states or private parties. It can invalidate the laws of EU members when they conflict with EU law. Its bench, which is appointed by member governments, consists of 25 judges and 8 advocates-general. Prior to 2004, the ECJ met as a full chamber for all cases, but it now may sit as a “grand chamber” of 11 judges. See also International Court of Justice.