The sources of international law are set by the International Court of Justice (ICJ) in Article 38 of the Statute of the ICJ in a hierarchical order:
- International conventions, whether general or particular, establishing rules expressly recognized by the contesting states.
- e.g. United Nations Convention on the Law of the Sea (UNCLOS) which established a legal framework to govern activities related to the global oceans.
- International customs, as evidence of a general practice accepted as law.
- e.g. Customary International Law of Diplomatic Immunity which refers to the practice of states in recognizing and granting immunities and privileges to foreign diplomats.
- General principles of law recognized by civilized nations.
- e.g.; Principle of Good Faith which dictates that agreements and treaties should be performed in good faith, for a fair and honest conduct among parties.
- Subject to the provisions of Article 59, judicial decisions and the teachings of the most highly qualified publicists of the various nations, as subsidiary means for the determination of rules of law.
- e.g.; The ICJ opinions, such as the Advisory Opinion on the Legality of the Threat or Use of Nuclear Weapons (1996).
- See also: On the Law of War and Peace, Hugo Grotius.
[Last reviewed in June of 2024 by the Wex Definitions Team]