By Dominic Casciani
Mr Mohamed arriving back in the UK, February 2009
Lawyers for Binyam Mohamed have accused the government of trying to manipulate a critical judgement on torture.
It has emerged the government's top lawyer protested to England's three most senior appeal judges about a paragraph highly critical of MI5.
Jonathan Sumption QC said comments about MI5's culture were "exceptionally damaging" and could be misconstrued.
The judgement was changed before being handed down but the foreign secretary denied his team had acted unfairly.
The judges have now agreed to hold a special hearing into whether they should amend the paragraph again.
Mr Sumption's letter to the three judges emerged in the aftermath of the Court of Appeal's decision to publish a secret summary of what the British government knew about Mr Mohamed's mistreatment while in US detention.
The top QC wrote to the lord chief justice, master of the rolls and president of the Queen's Bench Division two days before the
was handed down, urging them to reconsider one critical paragraph.
That paragraph had been written by Master of the Rolls Lord Neuberger, one of the country's top judges.
Mr Sumption said Lord Neuberger had made "some observations" about the "form" of the Security Service, MI5, that he said were "likely to receive more public attention than any other part of the judgements".
He said the words could be taken as meaning that MI5 "does not in fact operate a culture that respects human rights or abjures participation in coercive interrogation techniques".
published in full by the Guardian newspaper
, said that the paragraph could also be interpreted as suggesting that MI5 had misled parliamentarians and had a "culture of suppression" in its dealings with Parliament, government and the courts "which penetrates the service to such a degree as to undermine any UK government assurances based on the service's information and advice".
THE BINYAM MOHAMED AFFAIR
Ethiopian-born UK resident Binyam Mohamed was arrested in Pakistan in 2002. He was handed over to US agents and interrogated as a suspected terrorist. Courts say he was subjected to "cruel, inhuman and degrading treatment" before being secretly flown to Morocco. There, he was tortured and then flown to a secret prison in Afghanistan. He was later transferred to Guantanamo Bay and finally released in early 2009. The US told British officials that Mr Mohamed was being held and had been mistreated - and the Court of Appeal ordered the government to reveal what it knew. Mr Mohamed says MI5 was complicit in his torture because it could have intervened - but instead supplied questions to help his interrogators.
"If the observations in the draft judgement appear in the final version, the publicity likely to be given to them would be highly prejudicial to any criminal proceedings that might subsequently be brought [against anyone involved in the case] as well as the current civil proceedings brought against the UK government by Binyam Mohamed among others," Mr Sumption wrote.
"More generally, the master of the rolls' observations, which go well beyond anything found by the Divisional Court, constitute an exceptionally damaging criticism of the good faith of the Security Service as a whole."
The letter said the judges had not been in a position to rule that there was a "systemic" problem with MI5's rules for interviewing detainees and that there could be an "unprecedented breakdown in relations" between the courts and government.
Police are currently investigating the actions of the most important Security Service officer in the case, known only as Witness B. He denied wrongdoing when he gave evidence in courts from behind screens.
Jonathan Sumption QC: Led government appeal
Foreign Secretary David Miliband denied trying to manipulate the court.
"Our counsel submitted that the paragraph as originally drafted did not reflect the evidence that had been placed before the court," he said.
"He suggested to the three most eminent judges that they look at that paragraph again. They did so. They concluded after discussing it amongst themselves, not with us, that they should revise that paragraph so that it was properly based on the evidence that had been presented to them.
"That's a normal piece of legal practice. There is an air of desperation among those who would seek to turn what has been a completely proper and completely open way of proceeding with the court into some kind of unusual practice."
But Clive Stafford-Smith, the lawyer who represents Binyam Mohamed, said: "They were worried about public embarrassment.
"There has been a lot of damage to the credibility of the government and the Security Service throughout the process because they have been complicit in the torture and abuse of Binyam Mohamed. We have to learn from the mistakes of the past."