The Constitutional Dimension of the UN Charter Revisited: Almost One Quarter of a Century Later

The question of whether the Charter of the United Nations can be considered as the constitution of the international legal order was first examined by the present author here 25 years ago. At that time, it was noted that this issue raises a number of conceptual and theoretical problems that need to be briefly recalled in this paper. 25 years later, however, the question is whether the practical behaviour of States and the actual impact of their references to the Charter as a “constitution” confirm the validity of this thesis, which, it should be noted, originated in doctrine and was first put forward by scholars from federal States, including, in the first instance, Germany and the United States.
 In accordance with the wishes of the editors of this yearbook, the present article was written before the outbreak of Russia’s aggression against Ukraine on 24 February 2022. As a consequence, the examination of State practice both in terms of the authority conferred on the UN Security Council (organic test) and the norms it was able to adopt during that period as well as the way in which the International Court of Justice itself dealt with the Charter (normative test) led to a very nuanced conclusion as to the relevance of the constitutionalist theory in positive law. They also raise the issue of the criteria for appreciating what is a « good theory » one of them being for sure that is should not lead to any kind of dogmatism.
 Whatever the case, the very broad condemnation of the Russian aggression in Ukraine from the outset, notably by the United Nations General Assembly meeting in special session, together with the reactions of several other international bodies as well as heads of State or Governments, make it possible to note that the United Nations Charter is indeed still considered, at least by more than three thirds of the members of the United Nations, as the cornerstone of the international legal order. Does this necessarily mean that this instrument should be qualified as a “constitution” in the technical sense that some domestic public laws and political traditions mean it? The question still deserves to be asked. Here again, it very much remains an issue of definition; but the term is probably less important than the actual reality.