General opinion about the European Union which its legal nature controversial as an international subject to law is The Union has a suigeneris and a supra-national structure. As a result of member countries transfer the sovereign powers which are determined by the founding treaties to organs of the Union, Union's legislative, executive and judicial powers have emerged. In the theory of separation of powers, the legislative and executive bodies of the Union, particularly obliged to act together in the legislative field. The Union's judicial bodies act independently in fulfilling its judicial function, especially The European Union Court of Justice. Therefore, the European Union aims stability and cooperation between the legislative and executive forces and aims to independence in the judgment.