Chagos: Re-Awakening the Ghost of the 20th Century 

Ankit Malhotra considers the story of Britain’s last colony in Africa and the International Court of Justice’s Advisory Opinion on the Chagos Archipelago.  


‘Ghost’ is a concept largely evoked in the age of decolonisation, referring to the quest for self-determination; the re-awakening refers to the Chagossian quest to seek re-enjoyment of their land. Reference to this can be found in other contexts of decolonisation too. In addition, this summer, Mr Phillipe Sands QC’s course, ‘Colonialism: A Short History of International Law in Five Acts’ spoke directly to the colonial legacy at the Hague Academy of International Law. As Sands spoke, the images on the screen projected emotive illustrations of a small woman gradually advancing towards the Great Hall of Justice in The Hague. This note discusses the International Court of Justice’s Advisory Opinion (AO) in Legal Consequences of the Separation of the Chagos Archipelago from Mauritius in 1965 towards the ghost of decolonisation. The key tenet in the case was the determination of decolonisation and the sovereignty of a State. Sovereignty is embedded as a general principle of international law under Article 2(1) of the United Nations (UN) Charter and customary international law. In addition, it found resonance and formidable support in the United Nations General Assembly (UNGA) Declaration on the Granting of Independence to Colonial Countries and Peoples (UNGA Resolution 1514 (XV)). The Declaration is credited with condemning colonialism and all forms of the subjection of peoples to alien domination and exploitation as a denial of the UN Charter and fundamental human rights, as well as calling for the Member States to take steps to implement decolonisation.  


The Chagos Archipelago comprises a chain of 60 islands in the Indian Ocean. In 1965, the United Kingdom severed the Chagos Archipelago from neighbouring Mauritius to form part of British Indian Ocean Territory. What followed was a mass expulsion of the population from the Chagos Islands to Mauritius and Seychelles and in 1968 Mauritius gained independence. These forcible evictions cleared the coast, literally and metaphorically, for the British to lease the biggest island of the Archipelago, Diego Garcia. The British employed Diego Garcia as a military satellite to monitor the Indian Ocean and the Far East. Given the highly important military information available, natives’ entry was barred.   

The eviction of Chagossians was challenged in the British courts. The English Divisional Court and the Court of Appeal initially held that the Chagossian evacuation law was unlawful. Foreign Secretary Robin Cook, in 2000, withdrew the previous order , enabling the Chagossians to return home. However, the subsequent British Indian Ocean Territory (Constitution) Order 2004 reinstated the Chagos Islands’ restrictive measures. A second complaint was launched, claiming that this Order was likewise ultra vires. In addition, it was argued that the British Government breached the legitimate expectations of the Chagossians by passing the second Order after creating the impression that they were free to return home.  In Bancoult v Foreign Secretary (No 2) [2008] UKHL 61, the House of Lords held that the new Order was lawful and that considerations of national security and international relations prevented the Court from reviewing the new Order. The English High Court subsequently held that the prohibition, punishment and removal (including by the use of such force as is reasonable in the circumstances) of ‘unauthorized’ entry and presence was permitted in British Indian Ocean Territory.  In 2015, Bancoult sought leave to appeal to the UK Supreme Court on the basis that the ruling should be overturned owing to the non-disclosure of a 2002 feasibility assessment on Chagos Island resettlement, which was declined by the Supreme Court.

Designing the intelligence of a future day: International Law

All this changed in 2017 when the UNGA challenged the British control and claims to sovereignty over the islands by requesting an AO from the International Court of Justice (ICJ).  In its AO, the ICJ held that ‘the United Kingdom is under an obligation to bring to an end its administration of the Chagos Archipelago as rapidly as possible’. The Court recognised the principle of equal rights and self-determination of peoples as one of the purposes of the UN Charter, recalling the afore-mentioned UNGA resolution 1514(XV) and subsequent versions of it. Moreover, the Court noted that the adoption of UNGA resolution 1514(XV) represented a defining moment in the consolidation of State practice on decolonization’ and that ‘[b]oth State practise and opinio juris at the relevant time confirm the customary law character of the right to the territorial integrity of a non-self-governing territory as a corollary of the right to self-determination’. The Court considered that the peoples of non-self-governing territories are entitled to exercise their right to self-determination about their territory as a whole, the integrity of which must be respected by the administering Power. In India’s Written Statements, Ambassador Venu Rajamony emphasised the principle to uphold the process of decolonisation and respect for the sovereignty of nations. He also stressed that British inaction was the motivation for Mauritius to come before the ICJ through the UNGA. Australia, in contrast, contended that the Court is did not have  jurisdiction to issue an Opinion or, in the alternative, that the Court should not due to the lack of a ‘compelling reasons’ to do so. 

Next in the International Tribunal on the Law of the Sea (ITLOS) Special Chamber, the ICJ AO was considered in the maritime delimitation of Mauritius and the Maldives; the Special Chamber declared that the Chagos Opinion  had definitively resolved the contested sovereignty dispute. To clarify, the Special Chamber in this instance did not apply the AO in settling the dispute between Mauritius and the UK (which was not a party to ITLOS proceedings); it simply noted that the ICJ’s Opinion ‘has ramifications for the legal status of’ the Chagos Archipelago. Second, the ‘legal effect’ of the Opinion in resolving such a disagreement is not necessarily the same as the ‘legal consequence’ of imposing a judgement on the parties. Although it may be feasible for legally enforceable choices to have such an effect, it is not immediately obvious. Thus, irrespective of the binding nature of the ruling, the resolution of a sovereignty issue necessitates an additional legal step (of decolonisation), which appears to be absent here. Oxman warns (at [32]) that ‘it risks complicating…the ICJ’s exercise of its discretion about AO requests.’  

From a legal standpoint, a significant amount will rely on whether other judicial bodies adopt similar arguments. We may see more decisions awarding Advisory Opinions’ legal effect. Nonetheless, this may be an isolated incident; a bit of legal sorcery that allows the Special Chamber to disregard jurisdictional hurdles based on a discredited colonial argument. It would not be the first time courts with a clear moral imperative and legal context have deployed such legal imperfections.  In the present instance, it indicates that Mauritius has succeeded in going to a hearing on the merits and could soon add yet another favourable international legal ruling to its increasing docket. On a deeper reading, it becomes evident that the Chagos AO emphasises the determination of the crystallisation of ‘right to self-determination’ as a customary right, despite an objection from the British. However, the AO lacks an investigation of state practice and opinio juris. In the context of Resolution 1514 (XV), the ‘defining moment in the consolidation of state practise’ based on ‘its content and conditions of its adoption’ (para 5), we have a series of unsteady assertions and equally indeterminate conclusions. Customary international law’s colonial roots are hard to shake.

Impact and status quo

Immediately following the AO, it seemed that the status quo may be unchanged for the Chagossians. The UK Foreign Office issued a statement strongly defying the AO and emphasising its non-binding nature to escape enforcement or serious consideration. One officer went as far as to suggest that ‘the (military) defence facilities on British Indian Ocean Territory help to protect people around the world from organized crime and piracy’, thus adding weight to its importance at the cost of violating human rights. In scepticism towards the AO, a spokesperson for the UK Chagos Support Association noted that while ‘certainly (the AO) is a win for Mauritius, it remains to be seen whether or not this is a win for the Chagossian people’. However, there have been indications that the ghost is re-awakening. On 22 May 2019, the UNGA voted to adopt the AO.  

The International Court of Justice advised the UNGA in May 2019 to recognise Mauritius’ sovereignty over the Chagos Archipelago and to not recognise or implement any actions taken by or on behalf of the British Indian Ocean Territory. In response, as an UN-specialised agency, the Universal Postal Union presented the issue to its primary governing body, the Congress, for a vote. Consequently, the UPU will no longer register or distribute, postage stamps issued by the ‘British Indian Ocean Territory’. By doing so, they formally acknowledged the Chagos Archipelago as an integral part of the territory of Mauritius.


The imperial ghost has, time and again, haunted former colonial empires. However, what is the legacy of the AO? That question will be added to the long list of concerns of British foreign policy.  The unfavourable verdict in the Chagos Case has shaken the roots of British dominance and questioned her authority as a staunch voice of human rights and emancipation. On the other hand, slaying the ghost of self-determination has enabled the Chagossians to seek independence. However, all things considered, the resettlement of Chagossians is uncertain, as Bagchi notes, amid legalese and jurisdictional quagmires, the battle for ‘decolonization’ was certainly won but what the AO means for the islanders remains rather obscure and unsettled. 

Ankit Malhotra is reading his Masters of Laws at SOAS University of London as the Felix Scholar.