In classical international law, States alone were the makers and subjects of the law. Times have changed. Contemporary international law admits, not only States as its subjects but also individuals and international organisations; it controls not just the needs of States but also the needs of individuals as it continues to venture into areas which, in the classical era, were exclusively reserved to domestic law. The fact that international law now applies to entities other than States is no longer a subject of controversy both in theory and practice. On the contrary, the question relating to whether international law could originate from a source other than through the consent of States in the positivist sense of the law has remained a question of controversy. The question has been made more complex by the multiplicity of international institutions created by States and vested with authority to perform the functions entrusted to them under international law. The functions they perform influence the behaviours and expectations of both States and individuals; but the powers they exercise belong to the States which delegated the powers. Since the powers are delegated by States, it should follow that the powers be confined by the very fact of delegation to the functions for which the powers had been granted. Such powers cannot be used for any other purpose, perhaps. With this in mind, the question sought to be answered in this work is whether the powers granted to International Court of Justice to “decide disputes” – article 38(1) of the Statute of the Court) – implicates the power of judicial lawmaking. In other words, whether rules and principles arising from the decisions of the Court can be properly referred to as rules and principles of international law. The question becomes quite intriguing when placed within the context of article 38(1)(d) and article 59 of the Statute of the Court on the one hand, and the practice of the Court and of the States appearing before it on the other hand. Articles 38(1)(d) provides: “subject to the provisions of Article 59, judicial decisions and the teachings of the most highly qualified publicists of the various nations, as subsidiary means for the determination of rules of law.” By article 59: “The decision of the Court has no binding force except between the parties and in respect of that particular case”. Notwithstanding the language of the above provisions, it is shown in this work that like judges in municipal law, judges in the ICJ lay down rules and principles having legal implications for the decisions in subsequent cases as well as for the conduct of States, in general, regarding areas within the degrees of the settled case-law of the Court. It is accordingly argued that to the extent that rules and principles in the decisions of the Court are relevant as rules and principles of international law (in subsequent decisions of the Court) to the determination of international law rights and obligations of States, judicial decisions in article 38(1)(d) are a source of international law. This is notwithstanding the unhelpful language of paragraph (d) and the influence of article 59. Concerning article 59, the writer argues that the article has no bearing on the authority of judicial decisions in article 38(1)(d); its real function being to protect the legal rights and interests of States from a decision given in a case to which they were not parties.

L’instauration de la question prioritaire de constitutionnalité (QPC) conduit à repenser les rapports entre les juridictions suprêmes : Conseil constitutionnel, Cour de cassation et Conseil d’Etat. Elle met aussi en lumière les spécificités de la fonction de juger – et notamment l’exercice, par le juge, de son pouvoir d’interprétation. De fait, en créant un lien direct entre les trois juridictions suprêmes, la QPC brouille les frontières de leurs compétences respectives et les place dans une situation d’interdépendance qui impacte directement l’étendue et l’exercice de leur pouvoir herméneutique. La QPC s’avère donc être le vecteur – c’est-à-dire à la fois le support, et le révélateur – d’une concurrence très vive entre les interprètes. De ce fait, il n’est pas possible de considérer qu’un juge détient le « dernier mot » pour l’attribution d’un sens à la loi ou à la Constitution – ces deux textes étant conjointement et simultanément interprétés par l’ensemble des juges du système. Le contrôle de constitutionnalité a posteriori met ainsi en lumière l’existence d’un processus interprétatif à la fois continu et inachevé. L’étude de ce contentieux permet donc de mieux comprendre le travail herméneutique effectué par le juge – en donnant l’occasion de forger le concept d’interprétation normative. / The introduction of the The Priority Preliminary Ruling on the Issue of Constitutionality (QPC) leads to rethinking the relations between the supreme jurisdictions : Constitutional Council, Court of Cassation and Council of State. It also highlights the specificities of the judging’s function- and in particular the exercise by the judge of his interpretation’s power. In fact, by creating a direct link between the three supreme jurisdictions, the QPC blurs the boundaries of their respective jurisdictions and places them in a situation of interdependence that directly impacts the extent and the exercise of their hermeneutical power. Therefore, the QPC turns out to be the vector - that is to say, both the medium and the developer - of a very lively competition between the performers. Thereby, it is not possible to consider that a judge has the "last word" for the attribution of a meaning to the law or the Constitution - these two texts being jointly and simultaneously interpreted by the whole judges of the system. The QPC thus highlights the existence of an interpretive process that is both ongoing and uncompleted. The study of this litigation so lets understand the hermeneutical work done by the judge - by giving the opportunity to forge the concept of normative interpretation.