Disappointment has rippled through the ranks of Obama supporters in recent weeks, with the reviving of Guantánamo military courts and other backtracking in the War on Terror. More worrying still, in Afghanistan, Bagram Air Force Base has become Guantánamo’s evil twin sister — and a bloated twin at that, with a new $50 million prison bringing the number of inmates to more than 1,500, none of whom has ever caught sight of a lawyer or a legal right.

The Obama Administration has supported the Pentagon’s regressive Bagram policy, but this week may have witnessed the first sign of daylight in a very dark secret jail. The charity Reprieve had planned this week to file suit in Washington on behalf of an illiterate Afghan shepherd who had been locked up in Bagram for ten months without charges. But by yesterday he was expected to be free.

Captain Kirk Black, of the US Army, is the hero of the piece. He is a Swat team police officer in civilian life, mobilised into the military. I met him in Guantánamo in 2006; I was representing prisoners and he was guarding them. He was reassigned to Ghazni, Afghanistan, where his job included meeting the local shura council and trying to resolve their complaints.

According to Captain Black, Gul Khan was an innocent sheep farmer who had been swept up by the US military. They mistakenly thought he was Qari Idris, a Taleban leader. An American helicopter swooped down on Mr Khan, guns blazing; he was beaten, arrested and then banged up in Bagram.

The Obama Administration had two choices with people such as Gul Khan: one is to replicate Guantánamo. We can continue to ignore our 220-year commitment to due process and hope that the military eventually straightens out its own mistakes. But the extraordinary and catastrophic error rate in Guantánamo Bay is now clear, more than seven years on.

Certainly, the military has proven incapable of sorting the al-Qaeda wheat from the bystanding chaff. These are the figures: of 779 prisoners held to date, 550 have been released. After seven years, the remaining 229 should have been whittled down to the very worst “enemy combatants”: yet of the 33 men whose federal cases have been resolved so far, judges have ruled that an embarrassing 28 are entirely innocent. An 85 per cent error rate is not good enough even for government work. Meanwhile, the mere mention of Guantánamo inspires anger around the world — anger at our hypocrisy, for preaching law and practising lawlessness.

Matters have been proceeding no better in Bagram. In locking up Mr Khan without rights, Captain Black feared that the US merely managed to alienate the local population and amuse the real Qari Idris. By refusing to respect the rule of law, we have made life more dangerous for soldiers in Afghanistan, and minimised our chance of encouraging true change there.

The second choice is that we could try the programme that Captain Black proposed to his superior officers. He suggested that he ask the shura council to identify anyone who seemed to be the victim of an injustice. He would then — as in the case of Mr Khan — contact us at Reprieve. With no cost to the Government, we would secure pro bono assistance for the prisoner, and make a submission to the authorities at Bagram. Sometimes this would resolve the case. Sometimes it would not — in which case we would file a habeas corpus petition in America, again at no cost to the Government or the prisoner.

Captain Black’s offer could help to salvage America’s reputation, and perhaps truly win some hearts and minds. The per capita annual income of an Afghan is roughly $400: if he chose to give up eating, Mr Khan could hire a major US law firm for about an hour a year. Captain Black could promise free legal assistance to those who believe they have been treated unfairly. He believes — and who could honestly disagree with him? — that his work would do more for the safety of his fellow soldiers than wielding a gun.

The military’s response was to tell Captain Black that he was forbidden from doing anything further on the case, or to comment on it. The hero was muzzled. It seemed as if the only recourse was to challenge Mr Khan’s detention in the US courts.

But rather than simply lock horns with the Government in court, we wanted to give the Obama Administration an opportunity to do the right thing. After weeks of silence, on Wednesday our patience ran thin. A colleague was in the process of delivering the lawsuit to the Washington court when the call came — Mr Khan would be released to the care of the Red Cross the next morning.

Conceding an error in one case does not change a national policy — for either America or the UK. Captain Black’s offer still stands: does the Obama Administration have the courage to seek true change? Will his British allies agree to a similar plan in Helmand province? Or should we expect Afghanistan to be forever bound in the miseries of Bagram, Guantánamo’s evil twin?

Clive Stafford Smith is the director of Reprieve, the UK legal action charity

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