Has the Sun Finally Set on the British Empire?

Some reflections on ICJ advisory opinion on Chagos Islands

by Punsara Amarasinghe and Anastasia Glazova

The fame of British Empire was once embellished around the corners of the world as the empire where sun never sets and its imperial majesty ruled the millions of lives regardless how they were brought under the colonial yoke. The end of two great wars saw eventually paved the path to dismantle British Empire yet the problems created by the colonial rule were unsolved and continued to undermine the decolonized states. The recent advisory opinion given by International Court of Justice over the status of Chagos islands in Indian Ocean generates number of questions in the realm of international law regarding the drawbacks created in decolonization process and the duplicity of the concept if self-determination in international law.


In the historic context Chagos islands always have been an integral part of Mauritius but however three years prior to granting independence to Mauritius Britain detached Chagos islands from Mauritius and created it a part of the territory known as British Indian Ocean Territory. Between 1967 and 1973 the inhabitants lived in Chagos islands were forcibly removed and thus far they have been impeded by British law to enter the territory. The issue on the sovereignty of Chagos islands has lasted for decades as an unsolved riddle of colonialism whereas Mauritius always insisted the Chagos islands a part of their sovereignty despite British were reluctant to relinquish it, even the initial efforts made by Mauritius to bring the case before ICJ was not successful in the 80 decade. Nevertheless after envisaging a serious of attempts along with the assistance of African Union, 2017 United Nations General Assembly passed a resolution referring the issue to the advisory opinion of ICJ. The two fundamental questions General Assembly put forward before were that whether the decolonization process of Mauritius was completed when it was granted independence in 1968 and secondly what are the consequences emerging from modern international law before the continues presence of Britain in Chagos islands.

The issue of decolonization seems to be the most interesting legal issue arising from the advisory opinion of ICJ due to the fact that court has viewed the decolonization of Mauritius was not complete as it was not in accordance of the right to self-determination of the Mauritius people. Bringing the idea of self-determination into further evaluation becomes a pertinent issues as the very idea of self-determination always been a double edged sword. Especially in the post-colonial context dialog between West and newly independent states in Global South regarding understanding self-determination always have been different and the notion of self-determination appreciated by Third World was based on preserving their external integrity without getting subjected to any foreign force. As a matter of fact it was a quite understandable position as many of Third World countries had emerged from years of colonial domination and it paved the way for them to concern about external self-determination as their prime concern. However in examining court’s approach to assess the scope of right to self-determination in its advisory opinion was akin to the Declaration on the Granting of Independence to Colonial Countries and Peoples adopted by the UNGA Resolution 1514(XV) in 1960 (Resolution 1514). 

The Resolution 1514 declares that the ‘subjection of peoples to alien subjugation, domination and exploitation constitutes a denial of fundamental human rights…’, and all such peoples ‘have the right to self-determination’ whereby ‘they freely determine their political status and freely pursue their economic, social and cultural development’. The trivial question encountered in discussing the self-determination was whether it was a part of customary international law when the UK granted independence to Mauritius in 1968. However it is rather ironic that UK being the forefront colonizer in early 20th century had appeared for the right of self-determination of Sudanese people as their legal entitlement, in its effort to counter Egyptian claims on the Sudan in 1947. In its advisory opinion court seemed to have generally relied on the number of general assembly resolutions in deciding the scope of self-determination in international law. In fact the lethargic position adopted by Court without tracing the historical development of right to self-determination in opino juris and state practice has diminished the magisterial jurisprudential value that many international law scholars expected to hear from this advisory opinion. However court confined its opinion regarding right to self-determination of Mauritius people to UNGA Resolution 2625 (XXV) of 1970, on Declaration on Principles of International Law concerning Friendly Relations and Co-operation among States in accordance with the UN Charter and court confirmed its status in customary international law.

The court’s opinion on the incompletion of Mauritius decolonization should be taken into account as a monumental position shared by ICJ on the grim realities of colonialism which keeps haunting in 21st century. ICJ came to a conclusion that separation of Chagos Islands from Mauritius before the independence was an act done by British colonial rule without the genuine consent of Mauritius people. It seems to indicate that Court may have implicitly hinted that it would have been lawful if the separation was conducted after assessing the consent of people through something like a referendum. Court’s opinion was concluded by stating “the United Kingdom’s continued administration of the Chagos Archipelago constitutes a wrongful act entailing the international responsibility of that State”. This was the culmination of ICJ advisory opinion which brought a great triumph for Mauritius and a great blow upon the United Kingdom. In its concluding remarks Court invoked all UN member states have a responsibility to finalize the decolonization of Mauritius as right to self-determination stands as erga omnes obligation.

All in all the advisory opinion on Chagos islands brought some solace to the states eager to confront the colonial legacies and post-colonial burdens. As an example in its court proceedings Mauritius was heavily backed by African Union and India. One counsel appeared on behalf of African Union stated that “It is unthinkable that today, in the 21st century, there is a part of Africa that still remains subject to European colonial rule.” On the other hand the UK has been still adamant about their presence in Chagos island as they claimed that matter was resolved in 1982 in an agreement on compensation and also the UK has pointed out that right to self-determination was not applicable in international law till 1970’s , whereas the separation of Chagos island took place in 1968. 

The UK defense was rejected by majority of judges in ICJ and the only dissenting opinion was given by American judge Joan Donoghue and her contention was based on that this matter should not have been taken before ICJ as it stands as a bilateral dispute between Mauritius and the United Kingdom. It is evident that this advisory opinion has brought a severe pressure on the UK in the backdrop of ongoing Brexit hullaballoo. Even though the advisory opinions are not binding that it is hardly to assume the UK would completely disdain the opinion as it has already acknowledged that the manner of removing the inhabitants of Chagos islands was shameful. In that case the entire advisory opinion should be regarded as a significant victory for Chagossians and hall mark legacy in the international jurisprudence relating to concept of self-determination.

Punsara Amarasinghe is a PhD candidate in public international law at institute of law and politics at Scuola Superiore Sant Anna in Pisa Italy. He held a research fellowship at faculty of law Higher School of Economics in Moscow and served as a visiting lecturer in University of Colombo, Sri Lanka. He holds LL.M in public international law from South Asian University, New Delhi. He can be reached at punsaraprint10@gmial.com.

Anasatasia Glazova is a PhD candidate in at Faculty of Law, Higher School of Economics in Moscow, Russia. She worked as state legal officer in Vologda prior joining HSE and her research areas include International Human Rights Law, Law of the Sea and International Maritime Law. She can be reached at angla.1892@mail.ru.