Various sources of International Law

Various sources of International Law
The material sources of International Law are: (1) Custom, (2) Treaties (3) decision of arbitral or Judicial tribunals, (4) Juristic works. Under Art. 8(1) of the Statute of International Court of Justice, the court is directed to apply the following

1. International treaties
They are described as International conventions, whether general or particular, establishing rules expressly recognized by the contesting States.
(2) International custom, as evidence of a general practice accepted as law.

(3) The general principles of law recognized by civilized nations.
(4) Judicial decisions and teaching of the most highly qualified publicists of the various countries as subsidiary means for the determination of rule of law.

(2) International treaties: Treaties are of two kinds (a) Law-making treaties, and (b) Treaty contracts

(A) Law-making treaties: Law-making treaties lay down general rules binding on the majority of State. They are multilateral treaties, but every multilateral treaty is not necessarily law-making treaty. According to Briefly “Law-making treaties are those which a large number of Sates have concluded for the purpose either of declaring their understanding of what the law is on a particular subject, or of laying down a new general rule for future conduct, or of creating some international situation.” Since the middle of nineteenth century there has been an astonishing development of law-making treaties. The customary rules of International Law proved inadequate to meet the demands of industrial and economic changes. Therefore, we notice that since the world war so many treaties were concluded on re-cross, weights and measures, the protection of submarine cables, the suppression of slave trade, etc.

(B) Treaty contracts: Treaty contracts are not directly a source of International Law. Such treaties are generally bilateral treaties. They, therefore, constitute particular law, but nonetheless they lead also to the formation of International Law through the operation of the principles governing the development of customary rules in the following circumstances;-

i. A series or a recurrence of treaties laying down a similar rule may produce a principle of customary International Law. Such treaties are thus a step in the process whereby a rule of international custom emerges.

ii. It may happen with a treaty originally concluded between a limited number of parties and it may make a rule to be generalized by subsequent independent acceptance or imitation. Instances of this nature are “free-ships, free goods etc”. This rule is now generalized but it was concluded for first time in 1650 between Spain and the United Provinces.

iii. A treaty may be of considerable evidentiary value as to the existence of a rule which has crystallized into law by an independent process of development.

(2) International Customs
Treaties or conventions are of a recent origin. But until recent times, international law constituted for the most part of customary rules. These customary rules had generally ev9olved after a long historical process culminating in their recognition by the international community.

The importance of custom lies here that because there is no legislative machinery to enact International Law, custom plays an important part in laying down the rules of International Law. It is , therefore, cited before the world court as evidence of a general practice accepted as law. Most of the International Law consists of customary rules. They have evolved out of a long and continued practice. And they have thus become so mature and perfect that states do not hesitate in accepting the custom as a source of law. It was held in Paquete Habana case that customary rules of International Law grant immunity to small fishing vessels from belligerent action in time of war. In the Lotus case the court again resorted to the customary rules and held that there was no customary rule conferring exclusive jurisdiction in maritime collision cases on the contrary of the ships flag as regards all incidents on the ship.


(3) General principles of law
The International Court of Justice has been authorized to apply principles of law recognized by civilized states. These general principles of law are equity, natural justice and good conscience. General principles also include the principles of private law administered in national courts. Thus in Chorzow Factory case, the permanent court applied the principle of res judicator, and it referred to the general conception of law that any breach of an engagement involved an obligation to make reparation. In the Mavromattes Palestine Concessions case, the court referred to general principle of subjugating, and in the case of the diversion of water from the Meuse, the court held that it might apply Anglo-American equitable doctrines as being general principles. In order to deal with certain questions relating to the mandates and trusteeship systems. Judge MacNair applied the general private law doctrine of trusts. In the case Mazina and Naulila the arbitrators held that in absence of the express rules of international Law, it was their duty to apply the principles of equity to fill the gap left by express principles of International Law.

(4) Judicial decisions and teachings of the jurists
There are two judicial bodies whose decisions are subsidiary means for the determination of rules of law. These bodes are

(A) International Judicial decision
Art. 59 of the Statute of the International Court of Justice expressly provides that the decision of the Court has no binding force except between the parties and in respect of that particular thing.

(B) State judicial decision and decisions of International Arbitral Tribunals
The decisions of the State Courts may be treated as weighty precedents, or even as binding authorities.


The following are the other sources of International Law which though are not given under Art. 38 of the Statute of the International Court of Justice, but nonetheless they also lead to the growth and development of International Law.

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