Article 62 Intervention

By Quinn McKush*

The International Court of Justice is the judicial organ of the United Nations.¹ This judicial organ decides contentious proceedings between states and issues advisory opinions for authorized United Nations organs and agencies.² In contentious proceedings, only states that consent through special agreement, a treaty clause, or a declaration accepting the Court’s jurisdiction, may be parties before the Court.³ Under Article 62 of the International Court of Justice Statute (“ICJ Statute”), a third-state can intervene in a proceeding as a non-party to inform the Court of its “interest of a legal nature which may be affected by the decision in the case.”⁴ Since the statute was created in 1945, there have been fourteen cases involving Article 62 intervention, with only four successful interveners.⁵ In cases granting intervention, the Court has limited the scope of non-party intervention to prevent the intervening party from transforming a dispute between two consenting state parties into a multilateral dispute.⁶ Can Article 62 intervention allow a third state to enter a dispute without the consent of the original parties?

In Continental Shelf (Tunisia/Libyan Arab Jamahiriya), Malta sought to intervene in a delimitation case between Tunisia and Libya.⁷ Malta’s interest of a legal nature was in its geographical proximity to the area being delimited in the dispute.⁸ The Court found that Malta alleged a sufficient interest of a legal nature, but the Court also determined that Malta sought to intervene, “not objectively as a kind of amicus curiae, but as a closely interested participant intent upon seeing th[e]se issues resolved in a manner most favorable to Malta.”⁹ This would allow Malta to enter into the proceedings without assuming the obligations of a party to the case and without the consent of the parties present.¹⁰ Here, the Court denied Malta’s intervention.¹¹ In other cases, the Court has granted intervention but limited its scope.

In Land, Island, and Maritime Frontier Dispute (El Salvador/Honduras), Nicaragua sought to intervene in a case involving delimitation and territorial sovereignty in the Gulf of Fonseca.¹² Nicaragua’s interest of a legal nature that could have been affected was in the Gulf of Fonseca, because it considers it impossible for the Court to determine rights over the Gulf without considering all three of the riparian States in the region.¹³ The Court found this to be a sufficient interest of a legal nature to intervene, but only on one of the issues.¹⁴ The Court stated that Nicaragua has an interest in the decision on the legal regime in the Gulf, but Nicaragua has not shown such an interest which may be affected by any decision concerning the delimitation of those waters.¹⁵ Nicaragua’s intervention was limited to the Court’s determination on territorial sovereignty.¹⁶

The ICJ also protects parties to a dispute from third-state intervention by denying intervention where the third-state attempts to insert a new dispute between the parties.¹⁷ In Sovereignty over Pulau Ligitan and Pulau Sipadan (Indonesia/Malaysia), the Philippines sought to intervene in a territorial sovereignty case.¹⁸ The Philippines interest of a legal nature was in a 1878 Sulu-Overbek lease agreement which gave them rights over North Borneo, a coastline neighboring the islands at issue in the dispute.¹⁹ The Court reasoned that the stated legal interest does not lie in the islands at issue, but over a neighboring coastline that is not at issue between Indonesia and Malaysia.²⁰ Accordingly, allowing the Philippines to intervene would insert a new dispute between the parties because the Philippines’ interest of a legal nature is not already at issue in the original dispute. The Court denied the Philippines’ intervention application.²¹

While intervention may be a vehicle that states could misuse to insert themselves into a dispute without the consent of the parties, the Court has successfully prevented this by denying applications by third states that do not objectively inform the Court as a kind of amicus curiae, limiting the scope of intervention, and preventing third states from inserting new disputes between the parties. Parties to a dispute are also protected by the Court’s preference not to grant intervention applications, as only four applications have been granted since 1945. Accordingly, Article 62 intervention does not allow a third state to enter a dispute without the consent of the parties.

*Quinn McKush, J.D. Candidate, University of St. Thomas School of Law (Symposium Editor).

1. U.N. Charter art. 92. ↩︎
2. The Court, Int’l Ct. Just., https://www.icj-ci%5Bj.org/court (last visited Apr. 3, 2026). ↩︎
3. Statute of the International Court of Justice, art. 34, 35, 36, June 26, 1945, 33 U.N.T.S. 993. ↩︎
4. Statute of the International Court of Justice, supra note 3, art. 62. ↩︎
5. See generally North Sea Continental Shelf Cases (Ger./Den.; Ger./Neth.), Judgment, 1969 I.C.J. 3 (Feb. 20); Nuclear Tests (Fr. v. Austl.), Judgment, 1974 I.C.J. 253 (Dec. 20); Continental Shelf (Libya v. Malta), Judgment, 1985 I.C.J. 13 (June 3); Military and Paramilitary Activities in and Against Nicaragua (Nicar. v. U.S.), Judgment, 1986 I.C.J. 14 (June 27); Land, Island and Maritime Frontier Dispute (El Sal./Hond.: Nicar. intervening), Application by Nicaragua for Permission to Intervene, Judgment, 1990 I.C.J. 92 (Sept. 13); Sovereignty over Pulau Ligitan and Pulau Sipadan (Indon./Malay.), Application by the Philippines for Permission to Intervene, Judgment, 2001 I.C.J. 575 (Oct. 23); Land and Maritime Boundary between Cameroon and Nigeria (Cameroon v. Nigeria: Eq. Guinea intervening), Judgment, 2002 I.C.J. 275. (Oct. 10); Jurisdictional Immunities of the State (Ger. v. It.: Greece Intervening), Judgment, 2012 I.C.J. 99 (Feb 3); Whaling in the Arctic (Austl v. Japan: N.Z. intervening), Judgment, 2014 I.C.J. 226 (Mar. 31); Sovereignty over the Sapodilla Cayes/Cayos Zapotillos (Belize v. Hond.; Guat. intervening), Application by Guatemala for Permission to Intervene, Judgment, 2026 I.C.J. 185 (Mar. 19) (cases involving third-party intervention under Article 62). ↩︎
6. See generally Juliette McIntyre, Procedural Values in the Intervention Procedure at the International Court of Justice, 1 Ukrainian L. Rev. (2022) (arguing the Court’s practice allowing third-party intervening is guided in-part by party autonomy). ↩︎
7. Continental Shelf (Tunis./Libya), Application by Malta for Permission to Intervene, Judgment, 1981 I.C.J. 18 (Apr. 14). ↩︎
8. Id. at ¶ 13. ↩︎
9. Id. at ¶ 31-32. ↩︎
10. Id. at ¶ 32. ↩︎
11. Id. at ¶ 37. ↩︎
12. Land, Island & Maritime Frontier Dispute (El Sal. v. Hond.), Application by Nicaragua for Permission to Intervene, Judgment, 1990 I.C.J. 92 (Sept. 13). ↩︎
13. Id. at ¶ 37. ↩︎
14. Id. at ¶ 72. ↩︎
15. Id. at ¶ 105. ↩︎
16. Id. ↩︎
17. Sovereignty over Pulau Ligitan & Pulau Sipadan (Indon. v. Malay.), Application by the Philippines for Permission to Intervene, Judgment, 2001 I.C.J. 575, ¶ 35 (Oct. 23). ↩︎
18. Id. ↩︎
19. Id. at ¶ 41. ↩︎
20. Id. at ¶ 89. ↩︎
21. Id. at ¶ 95. ↩︎