The application of the principle uti possidetis juris to the dispute between Benin and Niger

Abstract

It was not the first territorial dispute between former French colonies that was resolved by the International Court of Justice. The Court has followed its established practice in respect to the application of the principle uti possidetis juris and effectivités. Still, new facts provoke new judicial statements relevant for the principle. So, the Chamber emphasized that the uti possidetis juris principle requires not only that reliance be placed on existing legal titles, but also that account be taken of the manner in which those titles were interpreted and applied by the competent public authorities of the colonial Power, in particular in the exercise of their law-making power. It sharpened the focus on colonial law as exclusively relevant for an application of the uti possidetis juris principle, excluding any application of the rules of international law. In spite of the fact that the Chamber intended to resolve the case only by the application of the principle uti possidetis juris and effectivités, certain references in respect to general practice concerning river borders as well as in respect to the principle of legal certainty were necessary.