The existence of interactions between different but overlapping legal systems has always presented challenges to black letter law. This is particularly true of the relationship between international law and domestic law, and the relationship between federal law and the laws of individual federation members. Moreover, some organizations have created their own supranational constitutional systems. The United Nations Charter is the best known and is often referred to as the 'World Constitution, ' but the European Court of Justice views the European treaties as a 'Constitutional Charter' for...