The ICJ Statute Article 38 displays the traditional Civil Law perception of case law, that it is a strong form of persuasive authority, but of no greater weight than the writings of experts in journals and books. It is hard for a Common Law trained lawyer to swallow this. Section 103 (2)of the Restatement shows a more modern understanding of the value of case law:
"(2) In determining whether a rule has become international law, substantial weight is accorded to
(a) judgments and opinions of international judicial and arbitral tribunals;
(b) judgments and opinions of national judicial tribunals;
(c) the writings of scholars"
The explanatory Comment states:
"Article 59 of the Statute of the International Court of Justice provides: ‘The decision of the Court has no binding force except between the parties and in respect of that particular case.’ That provision reflects the traditional view that there is no stare decisis in international law. In fact, in the few permanent courts, such as the International Court of Justice, the Court of Justice of the European Communities, and the European Court of Human Rights, there is considerable attention to past decisions.... ...In any event, to the extent that decisions of international tribunals adjudicate questions of international law, they are persuasive evidence of what the law is. The judgments and opinions of the International Court of Justice are accorded great weight. Judgments and opinions of international tribunals generally are accorded more weight than those of domestic courts, since the former are less likely to reflect a particular national interest or bias, but the views of national courts, too, generally have the weight due to bodies of presumed independence, competence, impartiality, and authority."
International Courts

International Law case law developed within a tradition of ad hoc tribunals established by agreements to arbitrate particular disputes, and a permanent "Court of Arbitration" was established at the Hague in 1899. This led to the creation of the Permanent Court of International Justice, established as an organ of the League of Nations in 1919. After World War Two, the PCIJ was replaced by the less ironically named International Court of Justice. A number of subject specific and/or regional institutions have developed international court systems within their structures. These include the courts related to the European Union, the Inter-American Court of Human Rights, the European Court of Human Rights, the Law of the Sea Tribunal, the WTO Tribunal, etc. The most recent truly international tribunal is the International Criminal Court, created in 1998.
While finding the case law of these institutions may seem relatively straightforward, some of the judicial systems are structured in ways that may seem odd to a novice. Opinions may be from an intermediate step rather than the final step in a proceeding. It is important to know the structure so you know the full authority of the text in hand.
An excellent new text which provides an introduction to the structure and procedure of all the major courts and similar institutions is the Manual on International Courts and Tribunals by Sands, Mackenzie, and Shany (London, Butterworths, 1999: JX1990 .A2M319 1999, 3rd Floor Reserve).
The International Court of Justice

This is the "world court", the single main tribunal for settling disputes between nations. It has a very useful website . Its decisions are considered the strongest statement on what international law is in the disputed situation.
In 1996 a fancy coffee-table book on the history of the court was published which serves as a good historical introduction:
The Yearbook of the ICJ (JX1976. C2 Y32, 2nd Floor) contains a range of useful information, including basic texts, a list of all its cases, a presentation of the structure and procedure of the court, biographies of its current justices, summaries of that year’s cases, etc.
Another useful introductory text is:
The official reporter is:
ICJ cases are reprinted in a number of places, including unofficial reporters, journals, International Legal Materials , etc. It is best to cite to the official text.
There have been a number of attempts at digests, including:
Many, if not all, of the cases through the middle 1980's are also digested in the Encyclopedia of Public International Law (Jx1226. En19, 3rd Floor Reference).
The ICJ’s predecessor under the League of Nations was known as the Permanent court of International Justice. Its decisions can be found in: