By Torin Douglas BBC media correspondent

Gavyn Davies, chairman of the BBC, drew the short straw.

And since the prime minister - for whom the queue started forming the night before - stepped down from the witness stand at 1250 BST, Mr Davies was sent in just before lunch.

The BBC chairman is an economist who has advised several governments, and has the reputation of playing a steady bat.

Nonetheless, Lord Hutton quickly picked him up on an unfortunate turn of phrase.

BBC chairman Gavyn Davies "soon got into his stride"

Mr Davies said he had thought Andrew Gilligan's report was one of those issues Today occasionally "trip over". He explained that he had meant "encounter".

But the BBC chairman was soon into his stride, insisting the row between the government and the BBC had been seen as routine, and dying down, until it was "reignited" by Alastair Campbell's evidence to the Foreign Affairs Committee.

"I felt this was an unprecedented attack on the BBC, mounted by the head of communications at 10 Downing Street," he said.

"He accused the BBC of lying. He alleged that the BBC had accused the prime minister of lying - something which I never believed the BBC had done.

"He said the BBC had followed an anti-war agenda before, after and during the Iraqi conflict.

Unknown e-mail

"I took this as an attack on the impartiality and the integrity of the BBC, done with great vigour."

This explained why the governors had decided they must defend the BBC's journalism, and its right to broadcast the story, at a special board meeting on Sunday 6 July.

Several concessions [were] made by Mr Davies, amid a generally robust defence of the BBC's handling of the issue

Mr Davies admitted they had not known of the e-mail from the Today editor Kevin Marsh, to his boss, saying the Gilligan story had been "marred by flawed reporting" and loose language.

But he did not believe they needed to.

They had received a considered assessment from the BBC's director of news that Mr Gilligan was an accurate reporter, with a track record of breaking reports of importance - albeit in a style of bold, primary colours rather than shades of grey.

As for the story itself, they felt it would be impossible for them to judge if it was accurate - but they could look at whether guidelines had been followed.

He said they had also admitted it would have been better if the government had been notified about the story in advance.

That was one of several concessions made by Mr Davies, amid a generally robust defence of the BBC's handling of the issue.

He was asked by Lord Hutton if he had known the original Gilligan report had been unscripted, and whether it raised issues of editorial control?

'Wrong'

"It does raise an issue in my mind about whether reports of this nature should be unscripted and that is something we will ask the news division to consider," he said.

He was asked about the e-mail sent by Mr Gilligan to an MP on the Foreign Affairs Committee, apparently revealing that Dr Kelly had been the source for the Newsnight reporter Susan Watts.

Tony Blair had phoned him to suggest the BBC should issue a statement saying it had been valid to broadcast the allegation, but to retract it

A friend of Dr Kelly's had revealed that a question about it from the MP had "totally thrown him [Dr Kelly]".

Mr Davies believed it would be wrong for a journalist to do such a thing but he did not see how Mr Gilligan could have done it, because he had not known Susan Watts' source.

He thought it was something the BBC director general Greg Dyke would want to bring to the board's attention later.

Mr Davies said he and the prime minister had both wanted to "reduce the decibel level" of the row.

Tony Blair had phoned him to suggest the BBC should issue a statement saying it had been valid to broadcast the allegation, but to retract it.

He said he could not do that - the BBC still believed it had reported its source accurately.

But he ended by expressing his deepest sympathy to the family of Dr Kelly, on behalf of the whole of the BBC, and he said the organisation would do its utmost to learn important lessons for the future.

Just what those lessons are will depend on the verdict of Lord Hutton.