BBC executive resigns after report into 'flawed' Savile TV investigation

His exit - as well as the replacement of Newsnight's editor and deputy editor - came as a critical report was published which revealed rivalries and factional in-fighting at the BBC.

The report - prepared by former Sky News executive Nick Pollard - said the decision to drop Newsnight's report into Savile's decades of abuse was "flawed" and plunged the BBC into "chaos and confusion".

It said the BBC's management system "proved completely incapable of dealing" with the issues raised by the axing of the story and "the level of chaos and confusion was even greater than was apparent at the time".

The BBC had been accused of dropping the report in order to protect tribute programmes which had been prepared about the late TV host and DJ, but Mr Pollard concluded this was not the case.

The report stated: "The decision to drop the original investigation was flawed and the way it was taken was wrong, but I believe it was done in good faith. It was not done to protect the Savile tribute programmes or for any improper reason."

The report was published at the same time as another review, by the BBC Trust, concluded that airing a 'Newsnight' report that led to Robert Alistair McAlpine being wrongly named as a paedophile had resulted largely from a failure by members of the team to follow the BBC's own editorial guidelines.

Mr Mitchell was criticised for removing the Savile investigation from a list of the BBC's potentially difficult programmes - known as the "managed risk programmes list".

The Pollard Report said the executive "could offer no convincing reason" why he had done so but if it had stayed on the list "some of the issues which have followed might well have been avoided".

BBC Trust chairman Chris Patten said the BBC accepted the review in its "entirety" and evidence would be published, apart from some redactions for "legal reasons".

Mr Pollard - whose inquiry has cost £2m (€2.46m) - told a press conference that "leadership and organisation seemed to be in short supply" at the BBC while it struggled to get to grips with the Savile scandal and its repercussions.

But he said the BBC was "eminently governable and will remain so".

Acting director-general Tim Davie said he accepted Mr Mitchell's resignation with "great sadness".

'Newsnight' editor Peter Rippon and his deputy Liz Gibbons are being replaced and have not been working on the programme for a number of weeks due to the fallout.

Mr Mitchell - who had been forced to step aside during the investigation - said today that he had decided to leave "with great sadness".

He said: "Given the strain over the past month since being told to stand aside from the job I loved, having endured the Pollard review process and now having read its criticisms, I have decided that it is in my interests and those of the BBC that I bring my career to a dignified end.

"Whilst I feel vindicated that the review has found that I put no undue pressure on Peter Rippon, I disagree with the remainder of Mr Pollard's criticisms in relation to me."

British Culture Secretary Maria Miller said the Pollard Report raised "serious questions" about the BBC's editorial and management issues.

She added: "It remains critical that we do not lose sight of the most important issue in this - the many victims of sexual abuse by Savile. I urge the BBC to now focus on the review into those abuses, and ensure it is swift and transparent."

Mr Pollard said that, despite the failings, he thought BBC journalism and trust in it would recover.

"There's no fundamental undermining of the BBC's journalism and any fall in that is temporary."

The BBC Executive said it would tighten up its procedures for difficult stories and there will be improved guidance and training for journalists about how and when material should be handed to police.

And in the longer term, the Executive said today that "aspects of the management and culture within BBC news must change".

Among the senior figures criticised in the Pollard report are former Director General George Entwistle and director of news Helen Boaden.

The review blamed in part an "apparent adherence to rigid management chains" for the failure to deal with the issue.

It said Ms Boaden's attempt to alert Mr Entwistle to potential problems posed by the story during an industry lunch was "too casual" and she is criticised for not taking "greater responsibility" as the crisis grew.

Mr Entwistle, who resigned after 54 days in the top job, was criticised for appearing to "have taken a long time to take any real control" of the problems at the BBC.

The review concludes that the BBC does not have to be taken down "brick by brick" but said the Director General's role as editor-in-chief needs to be examined.

It also said it "raises a question about the insularity of some people within the BBC" who are described as being unaware of wider industry practices.

In response, the BBC has said 'Newsnight' will get a new editor and deputy editor and added that incoming Director General, Tony Hall, will be asked to reform its "management culture".

The report paints an unflattering picture of relations between staff on Newsnight and in the wider BBC, saying the decision to cancel the story led to disagreements between show boss Peter Rippon and his journalists and "relationships... began to break down".

It found there was no "undue pressure" on Mr Rippon from his bosses to drop the story, but said his decision to do so "was seriously flawed".

It went on: "he made a bad mistake in not examining the evidence properly".

It also describes the background to his blog post on the issue, which was later corrected after being found to be factually incorrect, as "chaotic".

The evidence given to the review also reveals Mr Entwistle refused to speak to Newsnight reporter Meirion Jones off-the-record because he "didn't trust him to have an off-the-record conversation".

It also includes evidence from Ms Boaden that Mr Entwistle told her he would not accept her resignation and was going to make a public statement that would make "it impossible for Peter (Rippon) not to resign".

The report includes sections of an email sent to Mr Entwistle two years before becoming Director General, telling him an obituary for Savile had not been done because of "the darker side" to his life though Mr Entwistle told the inquiry he had not read it.

The review said the email, and others like it, indicates "there was knowledge, not just rumour ... about the unsavoury side of Savile's character" in BBC TV shortly after his death.

Mr Rippon said he did not agree with the review that his decision to drop the story was "flawed".

He said: "Of course, like everyone at the BBC connected with this case, I will learn lessons from what has happened, as I move on with my career. The BBC itself has an overriding responsibility to foster and support good journalism, and to respond proportionately when that journalism is challenged.

"Nick Pollard has raised questions about whether the BBC has been able to do this, and I agree with him that change is necessary."

Mr Entwistle said the report "makes clear that I played no part in determining the fate of the Newsnight exposé on Jimmy Savile".

He said: "Pollard's report underlines the fact that any managerial shortcomings relating to Newsnight's aborted Savile investigation were largely the result of unsatisfactory internal communications.

"These flowed from silos and other structural issues that I had identified when I became D-G and had begun work to resolve. I welcome Nick Pollard's recommendations in this area."

Speaking outside Broadcasting House in central London, Mr Jones criticised the BBC for pulling the story.

He said: "I hope the BBC takes measures to make sure nothing like that will ever happen again.

"What I do feel confident about though is the BBC has now taken measures to make sure that children are safe here."