Foley Hoag, International Legal Team Successfully Represent Republic of Mauritius Before ICJ

World Court Votes That UK Must Return Chagos Archipelago to Mauritius

March 1, 2019

Attorneys from Foley Hoag were prominent members of the international legal team that successfully represented the Republic of Mauritius before the International Court of Justice (ICJ), which agreed with Mauritius by a 13-1 vote that the Chagos Archipelago, severed from Mauritius and annexed by the United Kingdom in 1965, forms an integral part of Mauritius’ territory, and that the UK must return it to Mauritius “as rapidly as possible.” 

The ICJ, also known as the World Court, sits in The Hague and is the judicial branch of the United Nations. 

The Court issued its ruling in response to questions posed by the United Nations General Assembly on whether the decolonization of Mauritius, which achieved independence from the UK in 1968 minus the Chagos Archipelago, had been “lawfully completed,” and, if not, what legal consequences flow from that finding. 

The Court emphatically declared, in its Advisory Opinion rendered on February 25, 2019, that the decolonization of Mauritius was never completed because of the UK’s unlawful excision of the Archipelago, that the UK’s ongoing occupation of that territory is a continuing wrongful act, and that the UK must return it to Mauritius promptly.

Mauritius, which had been seeking the recovery of its severed territory for over 50 years, hailed the Court’s decision as a complete victory, and a triumph for the international rule of law. Also celebrating the result was the 57-member African Union, which called the ruling historic for all of Africa, because the Chagos Archipelago is the only remaining part of Africa that remains under colonial occupation.

Foley Hoag partner Paul Reichler was a co-leader of Mauritius’ legal team, along with Professor Philippe Sands, QC, of University College London. Other Foley Hoag lawyers on the team were partner Andrew Loewenstein, counsel Christina Hioureas, and associates Yuri Parkhomenko and Joseph Klingler.

Foley Hoag specializes in representing States before the ICJ and other international courts and tribunals. It is the world’s leading law firm in the litigation and arbitration of disputes between States. It is currently counsel in six other inter-State cases before the Court.

Although the Court’s Advisory Opinions, as distinguished from its Judgments in contentious cases, are not binding as such, they constitute a final and authoritative determination of the rules of international law applicable to a particular situation, in this case the unlawfulness of the UK’s severance of the Chagos Archipelago from Mauritius, its establishment of a new British colony on the territory, and its refusal to return it to Mauritius. Should the UK fail to adhere to the ruling, it will violate its obligations under the United Nations Charter to conduct its affairs in compliance with international law.

The UK has not yet announced when, or whether, it will return the Archipelago to Mauritius.

The matter now returns to the UN General Assembly for action demanding compliance with the Court’s ruling. Foley Hoag will continue to assist Mauritius in this process.

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