Auntie's bloomer over Gordon Brown

The BBC made a serious error in allowing Gordon Brown to be questioned about unsubstantiated health rumours

The health of the prime minister is a matter of legitimate public interest. When Winston Churchill was incapacitated by a stroke in 1953 his illness was covered up by Downing Street with the help of Fleet Street. It was a scandal but that is not an argument for every detail of a prime minister's health being made public as a matter of course.

Churchill was unable to do his job properly for months. Gordon Brown is clearly able to deal with the far greater physical demands of being prime minister half a century later. So the BBC can claim no public interest defence for airing rumours that until now had been largely the preserve of the blogosphere.

The BBC, along with all national newspapers, has become enthralled by the new media. Its correspondents are encouraged to blog themselves on top of all their other duties. That is all to the good. But it will be a disaster for British journalism if the wall between responsible, properly researched news reporting and the free exchange of gossip and unchecked rumour on the internet is breached. Good stories are being broken by bloggers and all power to them. But the BBC in particular must never forget its obligation to get its own corroboration and evidence before it broadcasts what is being said on the net.

Andrew Marr knocked an ugly hole in that wall and he was wrong to do so. His attempt to preface his question by saying that in America the president's full health record is public knowledge was an irrelevance. He was getting his defence in first for a question that he knew would test the limits of legitimate inquiry. What is incredible is that nobody in the BBC except the programme's editor, Barney Jones, was consulted in advance about whether it would be an appropriate line of questioning.

The BBC has been in one of its period bouts of agonised soul-searching ever since the Marr interview went out. Many of the most senior correspondents and interviewers are also here in Brighton and none that I have spoken to believe Marr was in the right. It is not just professional rivalry or even schadenfreude. It is not what BBC journalism should be about.

Lord Mandelson blames it on "extreme right wingers" in the blogosphere, although the allegations had already been referred to in print in the Independent as well as the Daily Telegraph. No 10 had explicitly denied the rumours and while a Downing Street denial doesn't prove the story is untrue it does demand that the BBC have good evidence before running with it.

Andrew Marr is a fine journalist and an asset to the Corporation. He is not part of any rightwing conspiracy. Nor, as some of his detractors inside and outside the BBC have been suggesting, is he trying to compensate for his previous New Labour sympathies and demonstrate his independence in anticipation of a Tory government. It was just a bad judgment call.

I am all in favour of brave and challenging journalism on the BBC as much as elsewhere. Its presenters should never be afraid to ask questions the politicians don't want to face. It likes its interviews to make news and they frequently do. But this was the wrong kind of news and quite rightly it is the BBC, not Gordon Brown, that now has to face some embarrassing questions about what went wrong.