The Chagos Islanders - Commons Library Standard Note

Published 20 April 2012 | Standard notes SN04463

Authors: Jon Lunn

Topic: Biodiversity, Environmental protection, Foreign and Commonwealth Office, Human rights

Between 1968 and 1973 the British Government cleared the entire Chagos Archipelago, officially known as British Indian Ocean Territory (BIOT), of its inhabitants as part of moves to build a US military base on the biggest island, Diego Garcia. The leasing arrangement with the US is up for renewal in 2016. Today, there are two main outstanding disputes arising from these events. One is between the Chagos Islanders (also called Chagossians or Ilois) and the British Government over the legality of the former’s removal and whether they have any right of return. The other is between the UK and Mauritius about the UK’s claim to sovereignty over the Chagos Archipelago.

Between 1998 and 2008, lawyers for one group of Chagos Islanders pursued the issue of their right of return to the Archipelago through a series of cases in British courts. This endeavour ended in 2008 when the Law Lords found narrowly in favour of the British Government. However, in 2009 the European Court of Human Rights resumed consideration of the case, which had originally been lodged in 2005 but held as pending while the British courts considered it. The European Court may rule on admissibility sometime in mid 2012.

Successive Mauritian governments have asserted a claim to sovereignty over BIOT, arguing that it was illegally separated from Mauritius before the latter gained independence in 1968. The UK has repeatedly rejected these claims, but has undertaken to cede BIOT to Mauritius when the territory is no longer required for defence purposes.

There has also been criticism of the previous British Government’s decision, announced on 1 April 2010, to establish a Marine Protection Area (MPA), in which commercial fishing was banned, around BIOT (with the exception of Diego Garcia). The Mauritian Government opposed the decision. This dispute has stymied bilateral dialogue. In December 2010, Mauritius lodged a complaint with the International Tribunal on the Law of the Sea, arguing that the MPA is incompatible with the UN Convention. This case may not be completed for several years.

Prior to forming the current Coalition Government, the Liberal Democrats and the Conservatives both said that they would review British policy on the Chagos Islands if they won office. However, policy remains fundamentally unchanged, with the Government saying that it is waiting for the ruling of the European Court. Many supporters of the Chagossian cause argue that, regardless of the outcome, there is no impediment to resettlement on the outer islands, which could eventually be returned to Mauritian sovereignty; livelihoods could, it is claimed, be supported by sustainable fishing and work for a scientific research station.

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