Scotland Yard is to investigate claims that former MI5 officers were complicit in the interrogation and torture of former Guantanamo Bay detainee, Binyam Mohamed, it was announced today.
The Attorney General Baroness Scotland said that she had asked the Metropolitan Police to carry an investigation "as expeditiously as possible given the seriousness and sensitivity of the issues involved".
Mr Mohamed alleges that an MI5 officer supplied questions to his interrogators when he was held and tortured at a secret site in Morocco following his arrest in Pakistan in 2002.
Prime Minister Gordon Brown, speaking from Brazil, said: "I have always made clear that when serious allegations are made they have got to be investigated. I have also been clear that this government does not tolerate or endorse torture."
Mr Brown added: "This is a matter that has been looked at by the Attorney General and has been referred to the police for investigation. Let's be also clear that this Government does not defend torture in any way.
"Once the case is passed by the Attorney General to the police it is for them to investigate the matter independent of any political process."
Mr Brown said he felt it was his job to say "on behalf of the British people" that they "respected the contribution" made by the security services.
"Our security services, in a period where terrorism has risen, where the threat of terrorism is very great, have done an amazing and courageous job," he said.
The Conservative leader David Cameron today called for a "targeted and clear review" into whether MI5 was complicit in torture.
He spoke after a meet and greet session with pensioners to promote his party's campaign to abolish tax on savings for basic rate taxpayers in Penwortham, Lancashire.
Mr Cameron said of the Attorney General's decision to permit the Metropolitan Police investigation into Binyam Mohamed's claims: "It's a disturbing development. I've been very clear: we have to get to the bottom of whether Britain was knowingly or unknowingly complicit in torture.
"Britain doesn't take part in torture, we don't encourage torture ... we've got to actually make sure that's what happens. It's important as well as having this investigation by the Attorney General we do need a more targeted and clear review to look at whether the right processes and procedures were in place."
He added: "I don't think the Government is doing enough to reassure Britain's good name and to get rid of this potential stain that hangs over us."
The former shadow home secretary David Davis said: "This demonstrates only too clearly that the evidence in the trial shows a very serious case to answer of complicity in torture.
"It is vital that this investigation does not simply select a low-ranking MI5 officer as a scapegoat, but establishes where the responsibility for approving these actions originated, no matter how high they go.
"Neither should this inquiry be allowed to suppress public consideration of the extent to which UK policy has been implicated and indeed reinforces the case for major public inquiry since Binyam Mohamed is only one of the people who have been tortured."
A Scotland Yard spokesman said: "We can confirm that the Commissioner today received a letter from the Attorney General inviting the Metropolitan Police Service to start an investigation into allegations that have been made in relation to Binyam Mohamed.
"A decision on how this will be taken forward will be made in due course."
Zachary Katznelson, legal director of charity Reprieve, which represents Mr Mohamed, said he was concerned secret evidence would be excluded from the investigation.
He said: "The Attorney General absolutely did the right thing today. It is critical that we get to the bottom of what was done to Binyam Mohamed and the role of any British official in his torture.
"But for this to be a proper inquiry the police have to be given access to all the information and that includes any secret information.
"Many of the documents related to Mr Mohamed's treatment have been classified either in the US or the UK and unless the police have access to all of them they will only see one tiny piece of the picture."
Mr Mohamed's claims were originally referred to Lady Scotland last year by Home Secretary Jacqui Smith after they surfaced in a High Court case brought by his lawyers.
Lady Scotland said that she and the Director of Public Prosecutions, Keir Starmer, had reviewed a "substantial body of material" relating to the case, including the testimony of a MI5 officer identified only as Witness B.
"I have concluded that the appropriate course of action is to invite the Commissioner of the Metropolitan Police to commence an investigation into the allegations that have been made in relation to Binyam Mohamed," she said.
"I have expressed to the Commissioner the hope that the investigation can be taken forward as expeditiously as possible given the seriousness and sensitivity of the issues involved.
"The conduct of the investigation will be a matter for the police, with advice from the Crown Prosecution Service.
"Any decision on whether any person should be charged with a criminal offence can only be taken following the police investigation on the basis of an independent assessment of the evidence and the public interest, in accordance with the Code for Crown Prosecutors."
Ms Smith said allegations of wrongdoing were taken seriously and pledged that the security and intelligence agencies would "co-operate fully" with the police investigation.
She said: "Following her consideration of the allegations of possible criminal wrongdoing which were made in the course of the Binyam Mohamed proceedings last year, the Attorney General has decided to ask the police to investigate these matters further.
"Wherever allegations of wrongdoing are made, they are taken seriously. That is why I asked the Attorney General to consider this matter.
"I'm grateful to her for this. The Government and the security and intelligence agencies will now of course co-operate fully with the police if asked to do so. You will understand that until the investigation is completed I cannot comment further or speculate on the outcome."
The announcement was welcomed by Liberty director Shami Chakrabarti, although she expressed concern that it had take so long to get the police involved.
"Whilst many will see the Attorney General's announcement as coming better late than never, the five month delay in reporting such a serious suspected offence to the police is far from an ideal example of respect for the law," she said.
"We look forward to the Metropolitan Police investigation into this particular case but the wider public interest still requires a full judicial inquiry into all British involvement in extraordinary rendition."
Amnesty International UK's head of policy and government affairs Jeremy Croft said: "Referring Binyam Mohamed's case to the police is the right thing to do, but it should be just the first step.
"We also need a separate independent inquiry into allegations from Binyam Mohamed and others that the UK colluded in their torture, rendition, illegal detention and other human right abuses.
"What we must not lose sight of here is that Binyam Mohamed's is far from being the only case where there are serious allegations that the UK colluded in the mistreatment or illegal detention of people from this country and elsewhere.
"We still need an independent inquiry with the powers to unearth any wrongdoing by UK officials during the 'war on terror"'.
Mr Mohamed - an Ethiopian national who became a British resident - was released last month by the Americans after seven years in detention.
He was arrested in at Karachi Airport in Pakistan in 2002 while trying to return to the UK following a trip to Afghanistan.
He alleges that he was tortured at a series of secret sites in Pakistan, Morocco, and Afghanistan including being beaten, scalded and having his genitals slashed with a scalpel.
In a statement made following his return to the UK, he said that "the very worst moment came when I realised in Morocco that the people who were torturing me were receiving questions and materials from British intelligence".
In September 2004, he was transferred to Guantanamo Bay, where he was held until his release last year.
The Liberal Democrats called for an independent judicial inquiry into torture and rendition allegations.
Foreign affairs spokesman Edward Davey said: "After months of delay, the Attorney General has at last made a clear decision".
He went on: "These are incredibly serious allegations of complicity in barbaric acts of torture and breaches of international law.
"There must be complete faith in the way the investigation is carried out if the public's trust, and Britain's standing in the world, is ever to be restored.
"However, the wider question of the Government's policy on rendition and torture throughout the Bush and Blair years will remain unanswered by this investigation.
"Only a fully independent judicial inquiry can get to the bottom of this and ensure that trust in government and international respect for Britain is restored."
The US authorities alleged that Mr Mohamed had undergone terrorist training at al Qaida camps in Afghanistan. Mr Mohamed claimed he only visited the country to kick a drugs habit and study Islam.
Last month, two high High Court judges reluctantly ruled that documents relating to his claims of torture could not be made public after the US warned that it would break-off intelligence-sharing if the material was released.
According to his note of an interview he conducted with Mr Mohamed in Pakistan in 2002, Witness B offered to use his influence with the US authorities to help him if he was co-operative.
"I told Mohamed he had an opportunity to help us and help himself. The US authorities will be deciding what to do with him and this will depend to a very large degree on his degree of co-operation," Witness B noted, according to evidence to the High Court.
"I said that if he could persuade me he was telling the complete truth I would seek to use my influence to help him. He asked how and said he did not expect ever to get out of the situation he was in.
"I said it must be obvious to him he would get more lenient treatment if he co-operated. I said that I could not and would not negotiate up front but if he persuaded me he was co-operating fully then and only then I would explore what could be done for him with my US colleagues."
According to court documents, Witness B made clear under cross-examination that he had been acting with the full authority of his superiors in MI5.
"I was always, whenever conducting an interview, careful to make sure that I had the clearance of my management to proceed and I did in this case," he said.
"I was aware that the general question of interviewing detainees had been discussed at length by Security Service management legal advisers and Government and I acted in this case, as in others, under the strong impression that it was considered to be proper and lawful."
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