The government's central argument for the creation of new generation of secret courts has been "blown out of the water" by the leak of highly sensitive British intelligence in the US, according to former shadow home secretary David Davis.
Ministers are stepping up plans to expand secret hearings into civil courts at the behest of MI5 and MI6, amid concerns that the US authorities will cut off the flow of intelligence if details emerge in open court.
But in a Guardian article, Davis calls on ministers to face down the demands after details were leaked in the US about a British double agent instructed by al-Qaida in the Arabian Peninsula to blow up an aeroplane with a highly sophisticated underpants bomb.
"This argument has been blown out of the water by last week's disclosures, which demonstrate that the American system leaks far more than the British ever could," Davis writes. "This leak happened not in the pursuit of justice but as a casually irresponsible piece of political spin."
Ministers have been under fire from civil liberty groups over plans to allow some material to be concealed from the public, the media and claimants during civil trials. The proposals are a response to the public airing of evidence during litigation brought on behalf of Binyam Mohamed and other former detainees in Guant?namo Bay.
The deputy prime minister, Nick Clegg, raised concerns about the plans in a letter to ministers on the national security council. Clegg said the courts should only be used in exceptional cases where there are national security concerns.
In the Queen's speech last week, the government announced an acceleration of the plans when it said that they would be included in a justice and security bill. The so-called "material procedures" would allow sensitive material to be heard in court in front of approved special advocates.
Davis argues that the arguments in favour of the secret courts are based on a "falsehood" ? that intelligence remains secret in the US. He quotes Mark Fallon, the deputy commander of the Guant?namo military interrogation team, who said: "In the US there are no secrets, only delayed disclosure."
Davis writes: "In the coming year, the government, at the behest of the intelligence agencies, is going to ask us to introduce a secret procedure into our civil courts for the first time in our history. It will allow the covering up of crimes ? such as complicity in torture ? that may have been carried out in our name. It is being justified as a way of protecting secrets from a country that makes a virtue of being even more open than we are, and which as a result lets slip more classified data in a day than our courts do in a decade.
"It is being argued on the assumption that our allies are naive, and are willing to compromise the fundamental values of our justice system in a war that is supposed to be in defence of those very values. None of these arguments stand, and so this proposal should fall."