Legal Consequences of the Separation of the Chagos Archipelago from Mauritius in 1965

Decolonization and its quite valid discontents lay at the center of this advisory opinion regarding the territory and populations of islands located in the Indian Ocean. Answering questions posed by the UN General Assembly, the International Court of Justice (ICJ or Court) concluded that because the Chagos Archipelago was detached from Mauritius as a condition of independence, the decolonization of Mauritius had not been completed in accordance with international law. The Court further ruled unlawful the United Kingdom's continued administration of the Chagos Archipelago and called upon all UN member states to aid completion of the decolonization process. Nearly unanimous—the sole dissenter on the merits was Judge Joan E. Donoghue of the United States—the advisory opinion contained significant pronouncements on decolonization, on the right of all peoples to self-determination, and on the formation of customary rules respecting both. It did so in a manner that implicated the ICJ's role as the judicial organ of the United Nations, in whose General Assembly and other political bodies the next episodes in the Chagos controversy seem destined to unfold.