Sir Ian Blair declared himself "a man of honour" today as he survived a motion of no confidence in his leadership of the Metropolitan Police.

Members of the Metropolitan Police Authority voted 15-7 against the motion which had been tabled by Conservative members and supported by Liberal Democrats.

Sir Ian won the support of Labour members of the authority and all but two of the independents who sit on it.

The vote was taken in the wake of the Stockwell shooting trial at which Scotland Yard was found guilty of serious failings in the operation that led to the death of Jean Charles de Menezes.

A separate report presented to the MPA revealed that the cost to the Met of defending the Stockwell case was £600,000, bringing its total bill for the trial – including a £175,000 fine and prosecution costs – to more than £1.1 million.

The authority was also told that £4.7million of expenditure by Met officers on corporate charge cards was not properly accounted for. A quarter of that money was made up of cash withdrawals, usually by officers on assignment overseas.

Members of Mr de Menezes’s family attended the emergency meeting of the MPA where the implications of the trial and issues of Sir Ian's leadership were debated publicly for more than four hours.

The Commissioner again told them of his personal regret over the death of Mr de Menezes.

"The case will live with me and my officers for the rest of our lives," he said.

Asking the authority for its support, Sir Ian said: "I am a man of honour. If I believed that what happened in this case made it appropriate for the commissioner to resign, then I would have gone. I would not have offered my resignation, I would have resigned."

He denied suggestions that having lost the support of one-third of his police authority he was a "lame duck" commissioner.

Sir Ian said: "I am not in a position of being 'in office but not in power'. I am in office, I will be in office and I will be in power."

The commissioner, wearing full uniform and accompanied by three of his most senior officers, sat through a frequently ill-tempered debate during which MPA members harshly criticised his record.

Bob Neill, a Conservative supporter of the no confidence motion, said the failures in Stockwell had been "so grave and so catastrophic" that Sir Ian should step down.

He said there had been a series of errors, including recording phone calls with the former Attorney General and criticism of media coverage of the Soham murders, which had damaged Sir Ian.

Mr Neill said: "Regularly, the Commissioner is now becoming the story and it is getting in the way of learning the lessons."

Lord Tope, a Liberal Democrat, said Sir Ian should follow the example of Paul Gray, who stood down as head of HM Revenue & Customs this week after the loss of the child benefit database by his staff.

Lord Tope said: "There is a difference between being responsible and taking responsibility... I've come to the conclusion that the head of this organisation has to take responsibility."

But opponents of the motion spoke out angrily at what they said was the politicisation of the debate about policing and the use of the Stockwell case for political ends.

Richard Sumray, a magistrate member of the authority, said: "This is about more than Stockwell. People are out to get the Commissioner."

Reshard Auladin said it would be wrong for the authority to allow Sir Ian to be hounded out of office.

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