I was astonished recently to learn that Ken Clarke, the Justice Minister whom I always thought of as something of a libertarian, should seek to clamp on the land of Magna Carta a Bill of wholesale restrictions on open justice.

He wants a special body of lawyers to sit behind closed doors conducting cases in which the accused cannot defend himself in time-honoured fashion. Incredibly, the accused will not even know with what he is charged nor have the right to face his accuser. He will be defended by a government-appointed lawyer he will never meet or speak with. And a Minister of the Crown, who may well be trying to protect himself or his department from well justified exposure, gets to decide whether the case in question merits this very special treatment.

Now, if this isn’t the very purest form of Kafka, then I’d like to know what is. Certainly every tinpot dictator of modern times would love it.

As you may have guessed from previous writings, the preservation of our ancient liberties is something of a hobbyhorse of mine. As I see it, we didn’t create, over centuries, the great edifice of The Common Law – admired around the world and used by over a quarter of it – only to see it dismantled in many of its essentials by a latter day band of political pygmies.

It is not as though I believe that it should be set in aspic, never to be changed. Some years ago I had deep misgivings when New Labour proposed to change the law of Double Jeopardy, whereby an acquitted person could never be tried on the same charge twice.

I came to believe that if science (DNA) could prove incontrovertibly at a later date that a guilty man had been acquitted then it would not be natural justice to let him continue to get away with it. There were, I considered, many good reasons for my earlier misgivings.

If, for instance, an oppressive government or police force were determined on a guilty verdict then it could keep on coming back for another bite of the cherry until it got the result it wanted.

Also, were the police to know that they could always have another try, they would not feel under the same compulsion to go that extra mile to ferret out all the available evidence the first time round. It would also be unfair on the acquitted person – who might believe that the powers-that-be were out to get him – to ask him to live under such a cloud of deferred retribution. But amendments were put in place that held to the double jeopardy principal except in the most serious of cases, so I was satisfied.

I have long felt that New Labour were cavalier in its attitude to the protections which The Common Law bestowed on us. When terrorism reared its ugly head in the aftermath of 9/11 they leaped to panic stations. They seemed to have forgotten that we, as a nation, had long experience of dealing with that particular sick and murderous element in society – thirty years, no less.

The IRA, of whom we are speaking, were, moreover, far more accomplished practitioners of the dark and terrible arts of mass murder than the Johnny-come-lately Jihadists who had grown up in our midst. Sadly, their bombs went off first time on nearly every occasion. The result was that, on a head count of victims, the IRA were light years ahead of their successors.

But New Labour saw it differently. They rushed through a whole range of measures which began the long assault on things we held dear: which had taken centuries of struggle to achieve. Now we have a new government of a different political hue, but it, too – inexplicably – continues the assault and even carries it into realms hitherto unthought-of. It has to be stopped.

Luckily, these new proposals have raised a great hue and cry from almost every quarter, including 57 of the 69 specially appointed lawyers who want nothing to do with it: bless their courage and probity.

Yet Cameron is supportive of the tragically misguided Clarke. No doubt the police and the security services would like – where they chose – to dispense secret ‘justice’ along with the hospital authorities, coroners’ courts, government Ministers and the Ministry of Defence – all of whom, it is proposed, at the minister’s discretion, can impose in camera hearings.

Were they to have had these powers, we would never had learned the truth with regard to the seven shots to the head, underground shooting of poor Charles de Mendez, mistaken for a terrorist; nor the lack of body armour and helicopters and the use of thin skinned vehicles which led to the death of so many of our brave soldiers; nor the lamentable toll of scandalous hospital deaths and shocking mistreatment of our old people; nor the truth about Princess Diana’s death; nor that of Victoria Climbié and Baby Peter; nor even, who knows, of the former Energy Secretary’s alleged wrongdoings. All of them bring acute embarrassment to the people and agencies involved and they would rather we knew nothing of their incompetence or couldn’t-care-less attitude.

Truth and openness, in my view, trumps every other consideration. Only in the most clear-cut threats to national security are we entitled to consider secrecy.

If David Cameron’s ‘Big Society’ means a smaller, less intrusive state and more power to the people then I am all for it. Power, inevitably, seeks more power. But I am not concerned how much power accrues to the people; the more the better: they can be trusted. But individuals and agencies must always be constrained, and a free press is there to help us to achieve that.

Servants of the state must also be held to account and answer for serious shortcomings. In industry, commerce and even sport, heads roll regularly: not so in the public sector. This must change. How often is abject failure rewarded not with the sack, but with promotion. This truly incenses the public.

Everybody knows what a failure the head of the Borders Agency has made of her job. And not just that, but the one before. Yet she gets promoted to head up HM Revenue & Customs, an agency failing almost as badly as her own and which desperately needs real and proven talent not failure.

What a way to do business. But that’s big government for you! Spitting in the eye of its paymasters at every turn.