Ten years is a long time. That a former British resident has spent every single one of the intervening days between February 2002 and today in a cell in Guantánamo, without answering a single charge or having had one day in court, is an affront to the concept of justice.

Shaker Aamer has lived the last decade of his life in limbo. He has gone from a young father in his mid-30s to a grey-haired man in his mid-40s in a cell in the detention camp in Cuba. During that time, he has been involved in protests against conditions at the camp, including hunger strikes, and has been subjected to periods of solitary confinement. He alleges that he has been subject to torture, both before his arrival and while there. He talks of days of sleep deprivation and beatings.

He is not alone in that limbo. His wife and children in London have been subjected to the same torturous wait. Without contact, without explanation, without recourse and seemingly without end. Shaker has never met his youngest child.

It is staggering to contemplate that the US government has perpetuated this injustice, and that successive administrations have flouted the law and the ancient principle of the right to a fair trial.

That this is the example set by the foremost power in the Western world is a matter of shame for America. It is responsible for a degradation of the collective moral authority of the US government and those who are its partners.

It is utterly unacceptable that this has been allowed to go on for so long. If Mr Aamer or any of the men remaining in Guantánamo have committed serious criminal offences, they should and must stand trial under a fair process which will ensure justice for victims of any criminal act. They must not languish there indefinitely.

The UK Government has repeatedly asked for Mr Aamer to be returned to the UK. William Hague must continue to exert all possible pressure to comply with that request, without yet more delay. It has already been too long, let us not mark yet another anniversary of this shameful scandal.

The writer is Director of Amnesty International UK