The Permanent Court of International Justice (PCIJ) was established in 1922. Article 36, paragraph 2 of its Statute reads:
The Members of the League of Nations and the States mentioned in the Annex to the Covenant may, either when signing or ratifying the protocol to which the present Statute is adjoined, or at a later moment, declare that they recognise as compulsory ipso facto and without special agreement, in relation to any other Member or State accepting the same obligation, the jurisdiction of the Court in all or any of the classes of legal disputes concerning:
(a) the interpretation of a treaty;
(b) any question of international law;
(c) the existence of any fact which, if established, would constitute a breach of an international obligation;
(d) the nature and extent of the reparation to be made for the breach of an international obligation.