The proper role of the doctrine of incidental questions in international adjudication

Abstract The doctrine of incidental questions functions to bring issues or norms within the purview of international courts and tribunals, even when such issues or norms may appear to lie beyond the scope of the parties’ consent to jurisdiction. Accordingly, there is a clear need to consider the contours and proper role of this important judicial doctrine. The following paper seeks to do exactly that by making two principal claims. The first is that the role of the doctrine of incidental question is one which is residual. Second, even when resort to this doctrine is necessary, because the international court may otherwise be frustrated in the fulfilment of its function, there exist two constitutive requirements in the doctrine which limit its scope, namely those of necessity and ancillarity.