IT’S RATHER unsettling being called a liar by a Cabinet minister. Especially when you are his biographer. In Lord Stevens’s memoirs, the former Metropolitan Police Commissioner suggests that David Blunkett is a lying, backstabbing bully. Having read Lord Stevens’s account of his relationship with the former Home Secretary, it is clear that, whatever else he may be, Mr Blunkett is indeed a liar.

My biography of David Blunkett was published last December. It caused something of a stir since, among other revelations, it contained his frank — and often withering — opinions about his Cabinet colleagues. The book also made clear Mr Blunkett’s view of the then Sir John Stevens. As I put it: “Blunkett considered Stevens to be a weak commissioner, lacking in judgment. He could talk a good game but was rarely able to deliver.”

Lord Stevens’s memoirs are a clinical demolition job on the former Home Secretary, not least because they expose Mr Blunkett’s willingness to tell an outright lie — about me — to defend his position.

In my book, I cited David Blunkett’s response to Sir John’s behaviour over the incident when, in June 2003, Aaron Barschak (the so-called “comedy terrorist”) made it past the police’s supposed watertight security into a party at Windsor Castle. Sir John promised root-and-branch reform and strong disciplinary action. And yet 11 months later there was a similar breach.

I wrote this: “Clearly, Stevens had failed to do what he had promised. Blunkett called the commissioner, pointing out that both their jobs were on the line . . . Blunkett was not impressed with Stevens’s response: more bluster, as he told his colleagues, and more empty promises.” I then wrote that Blunkett had told one of his advisers: “That man [Stevens] needs to start feeling the pressure he is under.”

Mr Blunkett had been even angrier when, in February 2003, he discovered that tanks had been placed around the perimeter of Heathrow. I quoted his description to me of the police’s decision: “It was male, macho, silly laddism. Boy’s Own comic stuff. They couldn’t help themselves.”

Sir John’s autobiography reveals that Mr Blunkett wrote to him on the day that my book was serialised. “[A]long came a two-page letter from Blunkett himself . . . apologising for all the rude remarks about me, and alleging that he had never made them. Indeed, he claimed that he had hardly spoken to Stephen Pollard, and believed, on the contrary, that I had been a splendid commissioner.”

Given that Sir John’s word is surely unimpeachable — and he presumably still has the letter from Mr Blunkett — only two conclusions can be drawn from the words in the letter. Either David Blunkett had no memory whatsoever of speaking to me; or he told the former commissioner an outright lie. Mr Blunkett said in his letter to Sir John that he “had hardly spoken” to me. Perhaps he simply forgot the six hours of on-the-record interviews, not to mention the days I spent with him, shadowing him at the Home Office and Labour Party conference.

From all the interviews I conducted for the book, the most oft-cited of his characteristics was his phenomenal memory. But sometimes Mr Blunkett does appear to have a truly terrible memory. By an amazing coincidence, however, his memory failures seem to happen only at especially convenient times. When the news broke of the speeded-up visa for his own son’s nanny, he claimed to have no recollection of having raised the matter with his private office. And now we learn that he has no memory of having spoken to me for my biography.

The issue is, in reality, black and white. Either Mr Blunkett said what I reported him as saying to me or he did not. In his letter to Sir John, he said that he did not — in which case I must have lied and made the quotes up.

Mr Blunkett’s accusation goes to the heart of my integrity — and, more importantly, his. If there was any truth to his claims, I would have behaved shamefully. No journalist can be allowed to get away with making up quotes.

There is only one person who has lied, and it is not me. Lord Stevens writes that he had been advised “never go to see him alone, but always take a witness”. I had a witness with me throughout my interviews: my tape recorder. I listened to the relevant interview again yesterday. His words are crystal clear. Mr Blunkett said everything I quoted — and a lot more which has yet to emerge. Indeed, as I interviewed him I would go out of my way to point out to him that the tape recorder was running, lest he forget and, being blind, be unable to see the red recording light. So not only is it plain wrong for Mr Blunkett to assert that I made the quotes up, it is also stupid. He knows that the interviews were recorded.

With the issue of Labour politicians’ willingness to lie now at the forefront of many people’s minds, the brazen insouciance with which he defamed me to Sir John can only worsen the public’s contempt for his party — and politics in general.

Mr Blunkett clearly regretted — albeit only after publication — being so frank with me. All I did was ask him questions, in his full knowledge that the interviews were for the book. My jaw dropped when I heard his answers. But those answers were his responsibility and no one else’s. In attempting to limit the damage by lying about his own words, he has merely raised the most serious question of all: whether or not he is fit for public office.

David Blunkett, by Stephen Pollard, is published in paperback today. Hodder, £8.99

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