Nothing raises the hackles of a journalist quicker than an accusation that his reporting is not up to snuff, is biased or is just plain wrong. What's more, it seems to pander to the widespread belief among non-media folk that all scribblers are generally untrustworthy and good for nothing.

In this respect, Flat Earth News, by Nick Davies, is gold dust. The book spreads its allegations like so much slurry, with attacks on the Daily Mail (no pictures of black people), The Sunday Times (using out-of-control private investigators) and most notably The Observer, which is accused of being little better than a government mouthpiece in the run-up to the war in Iraq.

All good knockabout stuff. Unfortunately, not only is it still possible to circumnavigate the Earth, but it is not at all certain that Flat Earth News's criticisms of specific newspapers hold water. In a book about newspaper standards, that is a serious matter.

Of course, some of Mr Davies's book packs a punch. When he talks about how the pack mentality allows news that is wrong to appear across a range of newspapers, he is right. He cites an example of the man who supposedly managed to insure himself against the emotional trauma of England performing poorly in the World Cup - an obvious nonsense that appeared in a range of titles via the Press Association.

It is also true that many newspapers remain reluctant to correct stories, and certainly with the same prominence that the original tale received. On a daily it is always easier to move on - but this does not mean any more than a tiny minority of what appears in any newspaper on any day is wrong. Mistakes do happen; what is troubling is that they can endure on the record when they should not.

Yet, what has caught the imagination of those writing about the book is the attack on The Observer, not least because Mr Davies is a regular contributor to the Sunday paper's sister title, The Guardian. Here is where the problems start, because it is not certain that what is presented to the reader as carefully researched and factual is not partial at worst, and highly contentious at best.

Mr Davies is scathing in his criticism of Roger Alton, who was Editor for almost ten years until he resigned last October. “There were times when Alton submitted copy to be included in leader comments, which other journalists believed had come from Alastair Campbell's e-mail messages”, Mr Davies writes. It is an extremely serious allegation to make about an editor, but no comment from Mr Alton is recorded. The assertion is allowed to remain unchallenged. Ring Roger Alton and he denies it; he says he had only a few e-mails from Tony Blair's former spokesman, all about trivial subjects such as Burnley Football Club.

That denial is not recorded. Indeed according to Mr Alton, a denial - or a comment from him - was not sought by the book's author. More to the point, Mr Alton says dismissively that he was last in touch with Nick Davies “eight or nine years ago,” and it is well known among Observer journalists that Mr Alton and Mr Davies are not, to put it mildly, close - a point that Mr Alton does not dispute. Friendship, of course, may not be relevant, but it adds an edge to the saga not apparent to the casual reader.

The book also alleges that Kamal Ahmed, who was then political editor of The Observer, advised Mr Campbell on how to present the “dodgy dossier”, used to promote the case for attacking Iraq. Here, Mr Ahmed's denial is recorded, but dismissed. Now, determining between claim and counter-claim in this, or any case, is not always easy, and all journalists do get too close to some sources at certain times. But whether a close relationship with Alastair Campbell amounts to an abdication of journalistic responsibility is debatable.

Other subjects of the book complain too. Senior executives of The Sunday Times, the sister title to The Times, say that its Editor, John Witherow, was not approached to defend the newspaper, which hardly indicates a balanced approach. Flat Earth News is clearly based on some inside sources, but in the emotional environment of a newsroom, many journalists find it easy to construct elaborate conspiracies as to why certain stories are favoured when often none exist.

Claims made in the book about The Observer have already been amplified by others. According to one headline in The Independent this week, the book contains “Damning allegations that, if true, bring disgrace upon The Observer”. Mind you, “if true” is an odd construction to use in a headline. Before the book appeared, The Daily Telegraph referred to “conspiracy theories about Alton being forced out over his politics” by executives at the anti-war Guardian. Was he? Paul Myners, the chairman of the Guardian Media Group, owner of both titles, denies it, but perhaps he too is wrong.

Yet The Guardian must have felt that the book was important, offering its writer a slot on its comment pages to promote it on Monday, though that piece did not refer to The Observer. But what is troubling is that if key parts of the book are arguably inaccurate, what does it say about the rest of the text?

dan.sabbagh@thetimes.co.uk

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