In their to implement international treaties – as the most important source of international law – member states are likely to face two questions:
1. As regards the interpretation of the concerned treaty, with whom does the competency and jurisdiction rest an international judicial authority or specific authorities of the member state? In the latter case, which authority will enjoy such competence: the executive power or domestic courts? While the intervention of the executive power may lead to injustice, exclusive competence of domestic courts may lead to an interpretation causing international responsibility and liability of the member state.
2. If there is a conflict between domestic law9s0 of the member state and (a provision of) the treaty signed by this state, which one would prevail? May the treaty abrogate the domestic law already enacted? May the treaty provision(s) be abrogated by a later enacted domestic law?
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