Ministers were facing demands last night to hold a public inquiry into revelations that the security services knew a terror suspect from Britain had been tortured by the CIA.
Senior judges ordered the Government to publish previously secret parts of a court document that showed Binyam Mohamed, a former Guantanamo Bay detainee, had been shackled, threatened and continuously deprived of sleep by his interrogators.
But it emerged yesterday that the judges had cut out even more damning parts of the judgment which said that M15 operated in a culture of suppression and disregard for human rights. The cuts were requested by lawyers for David Miliband, the Foreign Secretary.
The judgment was published after Mr Miliband suffered a humiliating rebuff to his attempts to censor the court papers detailing the treatment meted out to Mr Mohamed while he was held by the Americans in Afghanistan.
The Foreign Secretary argued that disclosing the details would undermine the trust between Britain and America over sharing of intelligence material crucial to the "war on terror".
But the Court of Appeal dismissed his argument. Upholding a previous court ruling, it ordered that the information should be published on the grounds that it had already emerged in an American court.
Delivering the ruling, the Lord Chief Justice, Lord Judge, said publishing the material would "not do the slightest damage to the public interest".
The previously redacted seven paragraphs were a summary by British judges of the intelligence received about the treatment of Mr Mohamed, who was referred to in the court papers as BM.
They said he had been "intentionally subjected to continuous sleep deprivation" and that the "significant mental stress and suffering" caused by this treatment was "increased by him being shackled in his interviews".
Mr Mohammed, who is 31, is an Ethiopian who was granted refugee status in Britain in 1994. He was arrested in 2002 in Pakistan on suspicion of being involved with terrorism and questioned by US and UK agents. He was "rendered" to Morocco and Afghanistan and sent to the Guantanamo Bay two years later.
He was released from the detention camp last year and, on his return to Britain, launched a legal action against the Government, claiming that UK officers were complicit in his ill-treatment. Jacqui Smith, when she was Home Secretary, referred the claims to police.
The court papers disclosed yesterday confirmed that he had endured brutal treatment and made plain that details were passed to MI5. They said: "We regret to have to conclude that the reports provided to the SyS [security services] made clear to anyone reading them that BM was being subjected to the treatment that we have described and the effect upon him of that intentional treatment."
They added: "It could readily be contended to be at the very least cruel, inhuman and degrading treatment by the United States authorities."
Mr Miliband conceded defeat after the Court of Appeal dismissed his appeal against an earlier court ruling that summaries of information received by the British security services from US intelligence should be disclosed. He authorised the publication of the contentious paragraphs on the Foreign Office website.
But it also emerged that ministers launched a successful last-minute attempt to remove some of the most damning comments about MI5 from the paperwork. A letter from Jonathan Sumption QC, for the Government, called for a paragraph warning that the security services did not have a culture of respecting human rights or of renouncing "coercive interrogation techniques" to be erased.
The judge's comments prompted such alarm in Government that the Foreign Office took the unprecedented step of secretly asking the judge to remove them from a Court of Appeal judgment, in direct contravention of a 400-year-old legal principle. Legal precedent prevents lawyers from secretly communicating with the courts.
The successful bid to remove the full detail of the judge's comments led to accusations that the Government had displayed "contempt" for the law by intervening in the legal process in a cynical attempt to stifle the truth.
His letter showed that the judges had originally intended to complain that MI5 had "deliberately misled" the Intelligence and Security Committee, the parliamentary body charged with overseeing its work.
They said the criticism particularly applied to an MI5 officer, known as witness B, who gave evidence in the Mohamed case. The words were taken out after Mr Sumption's complaint.
Mr Miliband told the Commons in an emergency statement that the Court of Appeal had upheld the principle that intelligence information should be shared between Britain and the US. But it had ruled that the secret evidence in Mr Mohamed's case could be disclosed as the information had already emerged in the US, the Foreign Secretary said.
He stressed that the treatment had not been carried out by British officers and ran contrary to this country's principles. He said allegations of MI5 collusion in the interrogation were already been investigated by police.
Opposition MPs, as well as human rights groups, demanded a full judicial inquiry into the case, with as much evidence as possible heard in public. But Mr Miliband insisted that the proper course of action was for the allegations to be considered by the courts.
Ed Davey, the Liberal Democrat foreign affairs spokesman, said: "Anyone who has followed this case closely ... will recognise that knowledge of the American use of torture remained in the secret service but was almost certainly passed on to the highest levels of Government."
-- with input from agencies
