The islanders enlisted a legal team including Amal Clooney to take their case to the Supreme Court Monday.
Britain evicted about 2,000 people from the tropical Chagos archipelago, a British colony, in the 1960s and 1970s so that the U.S. military could build an air base on Diego Garcia, the largest of the islands.
Almost a decade ago, Britain’s High Court and Court of Appeal ruled that they and their descendants could return to some of the 65 islands, though not to Diego Garcia. Those decisions were challenged by the government and overturned in 2008 by the Law Lords, then Britain’s highest court.
The Law Lords was replaced by the Supreme Court in 2009. The islanders’ lawyers argue that the earlier judgment should be overturned because the government of the time withheld information about a 2002 feasibility study into resettlement.
Edward Fitzgerald, a lawyer for the islanders, said that “there has been a significant injustice in the earlier proceedings, whether or not there was bad faith.”
The eviction of the islanders from their home halfway between Africa and Southeast Asia has long been controversial for Britain.
British authorities have expressed regret for the treatment of the islanders, but successive governments have blocked their attempts to return.
The key obstacle is the strategically important Diego Garcia base, which has supported U.S. military operations from Vietnam to Iraq and Afghanistan. In 2008, the U.S. acknowledged it also had been used for clandestine rendition flights of terrorist suspects.
Five Supreme Court judges heard the case Monday but are likely to reserve their judgment until later.