The decision to drop Newsnight's report into Jimmy Savile's decades long campaign of sexual abuse was "flawed" and plunged the BBC into "chaos and confusion", according to a review carried out by former Sky News executive Nick Pollard.

The document paints a picture of a top-down organisation with rivalries and faction fighting. 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 report found: "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."

Among the senior figures criticised in the Pollard report are former Director General George Entwistle and director of news Helen Boaden. The review said Ms Boaden's attempt to alert Mr Entwistle to potential problems posed by the story was "too casual" and she is criticised for not taking "greater responsibility" as the crisis grew. Mr Entwistle was criticised for appearing to "have taken a long time to take any real control" of problems at the BBC.

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". Deputy director of BBC News Stephen Mitchell has resigned from his position as a result of the fallout from the Newsnight problems, acting director-general Tim Davie said.

Also criticised was the Deputy Director of BBC News, Stephen Mitchell, who decided to remove the Savile investigation from the corporation's Managed Risk Programmes List (MRPL) - an internal mechanism to flag up stories that contain some element of potential danger including risk to the BBC's reputation. Pollard described that decision as "critical", adding: "It was important to establish why he had done this. Very unfortunately, he could offer no convincing reason". Pollard said that if it had stayed on the MRPL some of what followed "might well have been avoided".

The report was published at the same time as another review, by the BBC Trust, concluded that airing a Newsnight report that led to Lord 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. The broadcast on November 2 was a "grave breach which had been costly to all concerned" and resulted in the public being misled, the Trust's Editorial Standards Committee (ESC) found. I

The programme, which featured an interview with Steve Messham who said a senior political figure of the time abused him, led to the widespread naming of Lord McAlpine. The Tory peer, who had not been contacted by the programme, strenuously denied the allegations, launching legal action. The following week, Newsnight broadcast an apology, as well as apologies from Mr Messham, and Lord McAlpine later received £185,000 damages from the corporation.

A report by the BBC, led by the corporation's Scotland director, Ken MacQuarrie, found that Newsnight failed to complete "basic journalistic checks" and there was confusion about who had the ultimate responsibility for "final editorial sign-off". He found that the programme's editorial management structure had been "seriously weakened" as a result of the editor having to step aside over the Savile scandal, and the departure of the deputy editor.

BBC Trust chairman Lord Patten said the BBC accepted the review in its "entirety". He said the BBC will publish the evidence it gets from Mr Pollard with redactions for "legal reasons".