Once a Heathite, then a staunch Thatcherite, Ken Clarke has been an MP for three months longer than I've been alive, was a three-times loser of Tory leadership contests and has held five of the most important offices in British politics - Home Secretary, Health Secretary, Education Secretary, Chancellor of the Exchequer and most recently Justice Secretary.

But, despite his best efforts at a rearguard action to hold on to his job, today's reshuffle sees Ken Clarke shifted out of his role at Justice into an undefined role as Minister without Portfolio. It represents a new chapter in a long political career but it remains to be seen if it's nothing but an embarrassing demotion for a political giant of the last 25 years.

Over recent weeks, Ken has received plaudits from the right for the supposed good job he's done in slashing the Ministry of Justice budget yet is railed against for an approach which they perceive as 'soft on crime'. From the left, many see his questioning the inexorable rise in prison numbers as a refreshing change from the "prison works" mentality of the previous twenty years, but his ruthless slashing of legal aid led to accusations he betrayed his legal roots by removing access to justice for thousands of the most vulnerable in society.

And herein lies the complexity of Ken Clarke's legacy. True, he's been a pretty ruthless cutter of the Ministry of Justice budget. We know how he simply accepted the Treasury's quarter cut to his budget without so much as a whimper, and he has delivered this by destroying access to justice, slashing compensation for victims of crime, cancelling prison building and placing his faith in often untested payment by results methods.

But while he may appear to have cut spending, what he's actually done is displace spending. Slashing social welfare legal aid funding for law centres and Citizens Advice Bureaus doesn't simply remove the scale of demand by many of the most vulnerable in society -issues with housing, education and benefits won't just magically disappear but will simply fall to other arms of central and local government to deal with, but being off the books of the Ministry of Justice is all Ken cares about.

And squeezing more and more prisoners into a smaller and smaller prison estate, manned by fewer and fewer prison officers will do little to reduce re-offending, with those released unreformed at the end of their sentences going on to commit crimes that blight families and communities with enormous social and economic cost. So because of his short-sighted cuts, expenditure and costs will rise elsewhere across government and society.

Ken's economy is a false economy. It's a victory for ideology over reality. We saw this taken to its extreme in his aborted attempt to abolish the Youth Justice Board for the dogmatic reason that it was a quango, ignoring the startling success it has presided over in bringing down the numbers of young people committing crime and held on the secure estate.

Ken's whole raison d'être in the aftermath of the May 2010 election was delivering reduced reoffending by increasing support for addressing mental health problems, education and training, all on a shrunken budget. But it would take Superman to square that circle. And in this respect, it was more Clarke Can't than Clarke Kent. Prison numbers continue to rise, prison inspection reports continue to slam the absence of decent rehabilitation support, prison officer numbers continue to fall and our prison estate risks decay as he slashed the prison building programme to zero - not enough for even a cursory replacing of outdated facilities.

On human rights, within Government he's been a sometimes lone voice of support in our obligations towards the European Convention on Human Rights and the Human Rights Act. He has sought to face down - indeed, sometimes ridicule - the more outrageous posturing of his Cabinet colleagues on supposed and sometimes artificial abuses of our human rights legislation. With his departure, one of the few sane voices in the human rights debate within Government will be lost.

But Ken's always had this wider appeal than many other front bench Tory politicians. He's affable charm has struck a chord with many beyond the natural Tory hinterland. And in many respects, he's out of kilter with his own party - pro-European, pro-human rights legislation, broadly liberal on justice issues - as his amusing clashes with Teresa May over the past two years testify. In fact, his liberal instincts have led to him being dubbed the sixth Lib Dem Cabinet Minister in the coalition government - I'm not sure whether he sees this as a compliment or an insult.

It's a shame that his relaxed approach has been his Achilles heel over recent months. Being caught using loose language on rape on a Five Live phone-in might have been a genuine error, but the time it took for him to realise how offensive his outdated use of words had been demonstrated just how out of touch 1960s criminal barrister Ken Clarke had become with today's justice system.

However, David Cameron knows he has an uphill struggle to win a majority at the next General Election. Prime Ministers tend to hit their high watermark of popularity at their first General Election, which doesn't bode well for Cameron. To appeal to a broader electorate, Cameron needs people in his Cabinet in the mould of Ken Clarke. But keeping Ken in Cabinet for his easy and affable way with the voters is insulting to him and to many of the views he holds which are much at odds with mainstream Tory thinking. For all his criticisms and his recent sloppiness, he has always been a bittersweet Tory for many in the party - more popular outside his party than in it. Front bench Tory politics might just need his type if they are to avoid being kept out of outright power for a generation.

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