The International Court of Justice (ICJ) in February issued a non-binding advisory opinion rejecting the United Kingdom’s claim of sovereignty over the Chagos Islands, which London calls the British Indian Ocean Territory, and ruling that they should be returned to Mauritius. The court, at the request of the United Nations General Assembly (UNGA), considered two issues. First was whether the United Kingdom had lawfully completed the process of decolonization of Mauritius when that country was granted independence in 1968. And second, the court considered the legal obligations arising from the United Kingdom’s continued administration of the Chagos Archipelago.
In its decision, by thirteen votes to one (the U.S. justice, Joan Donoghue, gave the lone dissenting opinion) the court held that the United Kingdom did not lawfully complete the process of decolonization of Mauritius when it granted the country independence in 1968 because it had separated the Chagos Islands from the larger territory three years earlier. Mauritius had argued that it was forced to give up its control over the Chagos Archipelago in 1965 or its bid for independence would have been blocked by the United Kingdom. As a result, the court held that the United Kingdom is obligated to end its administration of the Chagos Archipelago “as rapidly as possible” and that the member states of the United Nations must cooperate in order to complete the decolonization of Mauritius.
While the case was ongoing, the United States argued that the court could not issue an advisory opinion unless both of the contending parties agreed to its jurisdiction, which the United Kingdom had not. This position displayed more desperation than legal nuance on the part of Washington. In matters of advisory jurisdiction, principal organs of the United Nations, including the UNGA, can ask for the ICJ’s opinion on matters of international law. In 2017, the UNGA passed a resolution to refer the Chagos matter to the court by 94 votes to 15. Among the 65 nations which chose to abstain were key allies of the United Kingdom including France, Germany, and Canada. This demonstrated a lack of international support for the United Kingdom’s position.
The United States is an interested party to the dispute between because it has a military base strategically located on Diego Garcia, which is the principal atoll of the larger Chagos Archipelago. In 1966, the United Kingdom agreed to a 50-year lease with the U.S. Department of Defense. In 2016, this lease was extended for another 20 years. To make space for the U.S. military presence, the United Kingdom expelled the inhabitants, close to 1,500 Chagossians, to Mauritius and the Seychelles between 1968 and 1973.
The archipelago has become important for the United States in the context of China’s current military activities in the region. The United States earlier used the base to launch strike missions during both Gulf Wars and the invasion of Afghanistan. The 12,000-foot runways on Diego Garcia are large enough to handle long-range bombers such as the B-1, B-2 or B-52, giving them operational capabilities over North Africa, the Persian Gulf, Afghanistan and the South China Seas
The Chagos Archipelago is important for the United Kingdom as well. It claims an exclusive economic zone (EEZ) from the islands and on this basis declared a marine protected area (MPA) around them. Mauritius challenged this MPA declaration in 2011 before a tribunal constituted under the United Nations Convention on the Law of the Sea. During the proceedings, Mauritius argued that the United Kingdom was not entitled to declare an MPA because it did not have uncontested sovereignty over the archipelago. The tribunal agreed and ruled that the MPA declaration was not in accordance with international law.
The UK government has downplayed the recent ICJ decision, with a Foreign Office spokesperson insisting, “this is an advisory opinion, not a judgement.” But Jeremy Corbyn, the leader of the opposition, has welcomed the outcome and said that it is time to “correct the injustice” and return the island to their rightful inhabitants. Mauritian prime minister Pravind Kumar Jugnauth meanwhile said, “This is a historic moment for Mauritius and all its people, including the Chagossians…Our territorial integrity will now be made complete, and when that occurs, the Chagossians and their descendants will finally be able to return home.”
At the same time, Mauritius has been quick to emphasize that it does not plan to disrupt the U.S. military presence on Diego Garcia, saying only that it wishes to be the party with which the United States or any nation must negotiate regarding the use of the Chagos Islands.
The handover of the Chagos Archipelago to Mauritius might be just, but whether it will happen and how much it will change on-the-ground realities remains to be seen. Even if the Islands are turned over to Mauritius, it has indicated it would continue the U.S. lease on Diego Garcia, making the return of Chagossians unlikely. The ICJ’s decision has, however, brought the debate about decolonization and its far reaching ramifications out into the open once again.