A MINISTER WHO HAS LOST his judgment is like a reviewer without a book: redundant. We need ministers to exercise their judgment, whether in bringing forward legislation or running their department. When that judgment deserts them, they serve — at best — no useful purpose. At worst, they become dangerous to the common good.

For almost all of his life David Blunkett’s defining characteristic was his impeccable judgment. Whether it was realising as a little boy that he needed to educate himself, defying the constraints placed on him by a headmaster who believed that blind children could aspire only to jobs as piano tuners or factory workers; whether it was shifting skilfully his positioning from being “loony left” leader of the so-called Socialist Republic of South Yorkshire to a pillar of new Labour; or whether it was knowing how to behave as a Cabinet minister who didn’t seem to behave like a Cabinet minister; Blunkett’s instinctive good judgment was the key to his rise up the political ladder.

There are many reasons for the destruction of his ministerial career. But they all have the same underlying cause — a sudden collapse in that judgment. Having an affair with another man’s wife, getting her pregnant, being too close to his son’s nanny’s visa application, rejoining the Cabinet when he was in no fit state to do so and “forgetting” to tell the Advisory Committee on Ministerial Appointments that he had been asked to become a director of a company that would later seek work with the department he went on to head; the old David Blunkett would have spotted the disastrous impact of any one of these.

The new David Blunkett, lacking his old judgment, remains convinced — as The Blunkett Tapes makes whingeingly clear — of the underlying rectitude of his actions. There is, though, one decision that he is happy to label a misjudgment. Indeed, despite competition from the above catalogue of misbehaviour, he had no doubt as to the “biggest single mistake of my life in frontline politics”. That was speaking to me.

In early 2001, I approached Blunkett about a biography I was planning to write. He had issued clear instructions to friends and colleagues not to co-operate with previous would-be authors. After lobbying him for months, I managed to gain his acquiescence. My book would be unauthorised, in that he had no say over the finished product, but not only would he not obstruct my research with friends, he would give me a series of on-the-record, taped interviews.

Some of the comments he gave me about his colleagues in those interviews turned out to be explosive. Remarkably, however, Mr Blunkett — a politician for well over 30 years, and a man who served in the Cabinet for almost nine — appears not to have understood the interview process. Journalist asks question. Politician answers question. Journalist publishes answers. His comments were, he complains, “put together in a collage, without context or explanation”. I ought, it seems, to have ignored what he told me over a series of on-the-record interviews, because they would prove embarrassing to him.

Certainly, as I heard his replies over the months I interviewed him, my jaw regularly dropped to the floor. I could not believe his frankness. Indeed, I was so astonished that I kept reminding him that the recorder was running; he had been so helpful to me that I did not want there to be any possibility of his not knowing full well that he was giving me on-the-record answers. But his supposed naivety is of a piece with the most striking impression to emerge from the nearly 900 pages of The Blunkett Tapes: that he is so convinced of his own righteousness that he lacks even the most basic self-awareness.

A fortnight ago, for example, extracts from his diaries were published in two newspapers. They were, one might say, a collage — without context or explanation. Not one of the ministers he quotes — revealing private conversations as well as Cabinet discussions — consented to having their words published.

One also wonders about his reliability as a guide to events. Blunkett writes that he wrote to me about an article last September, in which I pointed out that he had lied to Lord Stevens of Kirkwhelpington (the former Metropolitan Police Commissioner who was involved in a very public row with Mr Blunkett over the Pollard book). “I received no acknowledgment or reply,” he says. I received no such letter. He says the same thing about a letter he says he sent to Lord Stevens.

Perhaps both letters got lost in the post.

This week Martin Narey, former Permanent Secretary at the Home Office, wrote that Blunkett screamed hysterically at him that he could “machine-gun” rioting prisoners, a claim which Mr Blunkett denied.

Is there a flaw here? Should one believe the word of a civil servant with an unimpeachable record, of a former Commissioner of the Met, or of a man who twice ended up resigning from the Cabinet? It’s a tough one.

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