ICJ - Basis of jurisdiction

1. Special agreement

Article 36, paragraph 1, of the Statute provides that the jurisdiction of the Court comprises all cases which the parties refer to it. Such cases normally come before the Court by notification to the Registry of an agreement known as a special agreement and concluded by the parties specially for this purpose. The subject of the dispute and the parties must be indicated (Statute, Art. 40, para. 1; Rules, Art. 39).

2. Cases provided for in treaties and conventions
 

Article 36, paragraph 1, of the Statute provides also that the jurisdiction of the Court comprises all matters specially provided for in treaties and conventions in force. In such cases a matter is normally brought before the Court by means of a written application instituting proceedings; this is a unilateral document which must indicate the subject of the dispute and the parties (Statute, Art. 40, para. 1) and, as far as possible, specify the provision on which the applicant founds the jurisdiction of the Court (Rules, Art. 38).

3. Compulsory jurisdiction in legal disputes

The Statute provides that a State may recognize as compulsory, in relation to any other State accepting the same obligation, the jurisdiction of the Court in legal disputes. These cases are brought before the Court by means of written applications. The conditions on which such compulsory jurisdiction may be recognized are stated in paragraphs 2-5 of Article 36 of the Statute (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 or extent of the reparation to be made for the breach of an international obligation).

4. Forum prorogatum 

If a State has not recognized the jurisdiction of the Court at the time when an application instituting proceedings is filed against it, that State has the possibility of accepting such jurisdiction subsequently by  virtue of the rule of forum prorogatum.

5. The Court itself decides any questions as to its jurisdiction

Article 36, paragraph 6, of the Statute provides that in the event of a dispute as to whether the Court has jurisdiction, the matter shall be settled by the decision of the Court. 

6. Interpretation of a judgment

Article 60 of the Statute provides that in the event of dispute as to the meaning or scope of a judgment, the Court shall construe it upon the request of any party. 

7. Revision of a judgment

An application for revision of a judgment may be made only when it is based upon the discovery of some fact of such a nature as to be a decisive factor, which fact was, when the judgment was given, unknown to the Court and also to the party claiming revision, always provided that such party's ignorance was not due to negligence (Statute, Art. 61, para. 1). A request for revision is made by means of an application (Rules, Art. 99).

Declarations Recognizing the Jurisdiction of the Court as Compulsory

The States parties to the Statute of the Court may "at any time declare that they recognize as compulsory ipso facto and without special agreement, in relation to any other State accepting the same obligation, the jurisdiction of the Court" (Art 36, para. 2 of the Statute). 66 states have filed declarations with the Secretary-General of the United Nations. (2011)

Source: http://www.icj-cij.org