Abstract

Intervention is an incidental proceeding as one judicial procedure in the International Court of Justice（ICJ）. Two types of intervention are provided in the Article 62 and 63 of the Statute of the Court，the former of which is being discussed in this research. According to the Statute，a third party may request to intervene to proceedings when it considers the legal interest of which may be affected by decisions and then the Court may decide on that request. The institution is established during the period of the Permanent Court of International Justice while judicial practice is rare. There was no request of intervention as a third party until the 1970s. The Court rejected some intervention requests in the early stage，however，a substantial change has been made in 1990，which Nicaragua was permitted to intervene for the first time and since then，the Court has opened the door of the intervention.

After the success of Nicaragua，the Court permitted or rejected requests in different cases. The institution has been improved gradually in recent 40 years；standards related to third party intervention are created，nonetheless practice on some specific issues is still open to discuss in the Court. The essential condition for a third state to intervene is that the decision made by the Court may affect the legal interest of the third state besides precise objects of intervention offered by that state. The Court，through the intervention case of Nicaragua，definitely recognized both non-party intervention and party-intervention. Under the circumstance of party-intervention，jurisdictional basis of the third state is necessary otherwise it doesn’t meet the criteria of the Court on permission of intervention. The development of the Intervention ruled by Article 62 propels the Court to play a positive role in balancing the contradicts between party autonomy and interests of third parties，expanding its influence，realizing the judicial value of justice and promoting the international rule of law.

China has deep historical relation with the ICJ. Presently the Chinese judge is also on the bench of the Court，and by participation in the advisory case concerning on Kosovo’s issue China has made a big progress. All these backgrounds and preconditions make it possible for China to use intervention when proper. As far as the choosing of case type and intervention identity，it should be confined to cases without any relation to China’s political and security interests and it may intervene as a non-party. For one thing，it will contribute to protecting China’s legal interests in international affairs，for another China’s discourse power and its great image may be maintained by means of holding legal opinions and claims on the forum of the ICJ.

This research is composed of five chapters. Chapter I introduces the concept，historical development and legal resources of intervention in a general way. As Article 62 and 63 of the Statute share some common characters in these areas and there’re specific connections between the two，the analysis in this chapter has to be related to the institution origin and historical development of Article 63 although the focus of which is still on Article 62.

As the key part，Chapter Ⅱ，on the basis of the Statute and the Rules of the ICJ and judicial practice in the Court，points out that the legal interests and the purposes are general conditions for third party intervention as well as non-party intervention. In the case of party-intervention，the third state should have jurisdictional basis，i.e. jurisdictional link with the original party states in order to be consistent with the principle of state consent which is the fundamental principle of the Court’s jurisdiction. Party intervention is recognized by the Court but presently it is only a theory.

Chapter Ⅲ discuses some procedure issues such as the timing of the intervention claim and the subject of making decisions. In addition，some rights of the third state to be accessible to case documents，participating in oral proceedings and assigning ad hoc judges are also under discussion in different situations. All the three rights are not defenitly enjoyed by intervening states. Whether the application of intervention is permitted by the Court and whether the third state applies as a non-party or party may affect the above rights.

Chapter Ⅳ takes Jurisdictional Immunities of the State intervened by Greece as a case study with deeper analysis on the concentration of the Court towards intervention recently and the real effects brought by Greece’s intervention. The case has drawn much attention because of the international law issues of the merits itself and the successful intervention of Greece has caught more focus on details of the judgment on the legal interest.

Chapter V narrates from the perspective of value. The system of intervention has made positive contributes to both individual intervening states and the whole Court. Meanwhile，based on the relationship between China and the ICJ in many aspects and background of China’s participation in the Court，this part does some research on the possibility of China to intervene so as to provoke deeper thoughts on the institution.

Above all，it concludes that the intervention provided in Article 62 of the Statute of the ICJ has opened the door to third states with relatively precise criterias. Nevertheless，it is developing at the moment and some issues like the judgment of the requirement of legal interest of the third state still need to be clarified and strengthened by further judicial practice. As to China，intervention is one part of judicial proceedings of the Court and it is another way to participate in international judicial process that China may take some consideration.

Keywords：the International Court of Justice；incidental proceeding；intervention；legal interest；jurisdictional basis