In order to help the Chief Justice of Ruretania in the performance of the new role of ad hoc judge in a case before the International Court of Justice, we need to give guidance on how to assess and use the contents of an article published in the American Journal of International Law written by an eminent jurist, that was submitted by the parties as part of the materials to be used as part of the deliberations of the judges.
Article 38 of the Statute of the International Court of Justice lists the traditional sources of International Law, which include the international conventions of a general or a particular nature that are recognised by the parties to the case, international custom that is evidenced by general use and acceptance at law, general principles of law as accepted by civilised nations and as subsidiary means to establish these rules of law, the judicial decisions and the teachings of the most highly qualified jurists of the various nations.
At the time of drafting, the term “convention” was used to mean any sort of agreement, however with the passage of time this term was redefined to make a specific reference to multilateral treaties. Without any doubt these written, accepted and published agreements are the primary source of law-making at the international law level. The only situation where any other rule takes precedence over a treaty is where the rules forms part of the jus cogens doctrine. Jus cogens is a normative rule that is generally accepted by the majority of states and from which no other state can expect to be given a derogation.
It is also argued that the international custom as evidence of a general practice that is accepted by law is of equal validity and importance to the contents of treaties as new customs may replace previously agreed treaties and new treaties replace older customs.
Article 38(d) of the ICJ statute specifically states that judicial decisions and the teachings of the most highly qualified publicists of the various nations may be used as subsidiary sources and the court is entitled to refer to these publications. This is subject to the provisions of Article 59 of the same statute.
Article 59 states that the decision of the International Court of Justice shall have no other bearing or binding force except on the parties of the case in question. However as part of the court’s decision, reference to other judicial decisions and to previously published works of eminent writers may be made.
The works of prominent jurists and scholars are accepted only as secondary or subsidiary sources of international law but can be considered to be an essential element in the development of the rules that are included treaties, custom and the general principles of the law.
More recently, the acts or resolutions of the various international organizations are also being considered as secondary sources of international law.