EU Law-versus-Bilateral Investment Treaty Law and Public International Law: Impact on International Relationship of States and EU Solidarity

European Union (EU) is an association of European states having international legal personality and is therefore a subject of Public International Law. According to the provisions of the Treaty on European Union (TEU) 1992, EU was established to undertake and implement some common political, economic and social policies for the member states. For the sake of attaining this goal EU binds its member states by the Treaty of Accession and all other European Commission (EC) Directives from the moment any European state signs for the membership of EU. There are some instances in which EU member states after signing EU Accession Treaty have brought changes to domestic policies or legislations resulting into a breach of the norms of Public International Law and in some cases the provisions of previously executed Bilateral Investment Treaties (BIT). When such breaches were complained before international judicial forums, European Commission (EC) and European Court of Justice (ECJ) have actively tried to establish that in case of any clash between EU Law and Public International Law or BIT provisions, norms of EU Law will prevail. This work tries to expose this conflict of hierarchy between two sets of legal norms and how it may affect the international relationship of modern states.