The function that is characteristic of the judicial act in contributing to the development of Public International Law concerns the implementation phase of the international legal norms and has no direct impact on the normative-legal stage, which is an exclusive prerogative conferred to the states and international organizations as plenipotentiary subjects in the frame of international relations. However, we find that, in the process of analyzing the function of contribution to the development of International Law, the document issued by an international court is based on the principles of coherent development of the released jurisprudence and the degree of opposability of the judgments that may be invoked in respect of third parties (depending on the nature of the case). In this perspective, the judicial statement of an international tribunal, acquires a different meaning and importance for the contemporary legal order.