International Law, Intertemporal Problems

Parties to an international dispute occasionally disagree about the legal significance of acts, situations, or treaties that place in the distant past. The question thereupon arises whether to apply the international law that was contemporaneous with the acts in question, or whether to apply present international law. Often the legal rules have changed or evolved over the course of years. In the latter instances, the outcome of the dispute might well turn upon whether the old law or the current law is applied