THE great excuse, the shame-faced confessional that follows the political scandal, has assumed another new form.

For Charles Kennedy it was the whisky; David Blunkett cited issues of paternity; Peter Mandelson was once tripped up by money. Famously, in the case of Ron Davies, there was a moment of madness — now Mark Oaten has blamed his fall on the onset of baldness.

The former Liberal Democrat home affairs spokesman said yesterday that his dalliance with a male prostitute that provoked headlines about his “3-in-a-Bed Rent Boy Shame” was caused by a mid-life crisis.

Mr Oaten, who remains MP for Winchester, revealed himself to be a reluctant politician who fell prey to a self-destructive urge to crash his career. He disclosed that he was deeply troubled by the thinning of his hair, which he took to be a symbol of his disappearing youth.

“I doubt that, on its own, my dissatisfaction with politics would have prompted me to act as I did, but it coincided with something of a mid-life crisis,” Mr Oaten wrote in The Sunday Times.

“I was turning 40 and I really felt that I was losing my youth. The problem was undoubtedly compounded by my dramatic loss of hair in my late thirties.

“This really knocked me for six. Any television appearance would result in a barrage of e-mails, not about issues I’d raised, but about my lack of hair. Whether supportive or not, they all asked what had happened to my hair. It’s perhaps not surprising that I became more and more obsessed by its disappearance. For me it was a public sign that my youth had ended.”

Mr Oaten’s disgrace was plastered over the pages of a Sunday newspaper in January just days after he dropped out of the race to succeed Mr Kennedy as Lib Dem leader.

In his article he claimed that many of the lurid allegations about him were “extremely hurtful and just utter nonsense”, but he added: “There’s no point taking legal action. I did some stupid things and I’ve only myself to blame.”

He revealed the pain and difficulty of trying to explain to his wife, Belinda, what had happened, and of trying to get two young daughters away from the media spotlight. He recalled his wife’s anger as he fled the family home the morning before the story broke.

“Shortly before I went out of the back door, her calm at last gave way to fury,” he said. “ She tried to hit me several times and threw her wedding ring back at me — and who could blame her? “Over the next fortnight I slept in nine locations, running away when I heard the press were on my tracks. Waking up was the worst part of the day. Each time the true horror of what I had done, the hurt I had created, came flooding back.”

Mr Oaten said he had never had doubts about his sexuality until the stress of his frontbench job coincided with his mid-life anxiety.

“One of the contributing factors was my unhappiness at work,” he said. “Not a day went by when I didn’t consider throwing in the towel. I could never quite bring myself to resign . . . it’s as if I was daring the world to bring the whole thing crashing down.”

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