Governments of all stripes eventually come to resent the separation of powers, none more so than our present one, which has suffered several spectacular humiliations at the hands of the judiciary. But while lawyers (and we former lawyers) may cheer and congratulate ourselves on being guardians of eternal liberties, there is inevitably someone beavering away in Whitehall trying to come up with ways of remedying the situation.

The ancient office of coroner (that dates back to at least 1194) has been in the Government’s sights for a number of years and after the De Menezes case, not to mention the ten-year-long Diana, Princess of Wales, inquest, the eagerness for reform must be overwhelming. It is ironic, however, that a process that began with the Shipman Inquiry and the desire to make coronial procedures modern, open and accountable, has quickly evolved into a series of brazen attempts to emasculate them entirely.

The “trouble” with our coroners is that they are unique in our system of justice in being charged with seeking out the truth. More akin to a continental examining magistrate than a British judge, the coroner must find out the exact cause — the when, where and how — of an unnatural death. In cases where a death occurred in custody, at the hands of the police or in any other situation where public health and safety may be affected by the outcome of the inquiry, a jury is required.

What is more, a coroner’s jury is not only entitled to return a verdict of its own choosing, it may also add a narrative statement setting out in whatever degree of detail it wishes, the facts surrounding the death.

The De Menezes inquest is a classic example of how, using traditional methods, the Establishment sought and partially succeeded in managing the risk of an unpredictable and potentially damaging outcome. Prerogative powers vested in the Lord Chancellor were used to replace the Inner London South Coroner with a retired High Court judge, Sir Michael Wright.

Don’t forget that in 2006 it was the Assistant Deputy Coroner for Oxfordshire (no less), who brought the mighty US military to heel, and in the teeth of official lies and obfuscation extracted the cockpit tape from the US A10 aircraft that fired the fatal rocket at Lance Cpl of Horse Matty Hull. (A verdict of unlawful killing was returned in that case, but no charges have been laid.)

At the conclusion of the De Menezes inquest Sir Michael sought to prevent a repeat of the Matty Hull embarrassment by denying the jury the option to return an unlawful killing verdict — the one many suspect they might have returned left with the choice.

It is true that the coroner was entitled to tell them that in his view the evidence justified only an open or lawful killing verdict, but it is equally true that it was the jury’s constitutional right to return whatever verdict they wished. The eventual result was an uncomfortable non-conclusion: an open-verdict that hints at police culpability and leaves the way open for further judicial review.

This is exactly the sort of mess the Government’s various attempts to frame reforming legislation has been designed to prevent.

We haven’t yet seen the latest draft of the promised Coroner’s Bill, but recent attempts to frame draconian powers don't bode well: tucked away in the recent Counter Terrorism Bill — and thankfully winkled out by the Lords last summer — were provisions allowing inquests to be conducted in secret, without a jury and by a coroner specially appointed for the purpose where the Home Secretary deemed it “in the interests of national security, or in the interests of the relationship between the United Kingdom and another country, or otherwise in the public interest”.

In addition, a further clause allowed for the Home Secretary to intervene and render an inquest secret and juryless at any stage before or during its proceedings. If this were not enough, the original 2006 draft of the Coroner’s Bill sought to include a power for the Lord Chancellor to make regulations setting out categories of evidence a coroner would not be permitted to require to be produced at an inquest.

Such sweeping powers designed to exert political control over sensitive inquests are unlikely, even by sleight of hand, to pass into law, but the fact that they are considered desirable at all is deeply worrying.

Had such provisions been in place several years ago the Matty Hull inquest would have taken place in secret, without a jury and would have been presided over by a government appointee, not a provincial solicitor insensitive to the repercussions of his irresponsible truth-garnering. The De Menezes family would have sat in a court room devoid of journalists and jurors while a similar appointee would have dutifully assessed the evidence and given police officers the benefit of the doubt.

One day, when we grow up into a proper democracy, we won’t fear the truth because we will realise that hearing it, and quickly, is the quickest way to resolution and progress. In the meantime we need to jealously defend all aspects of our justice system — however anachronistic or ramshackle — which put the individual and the truth above all else.

Dr Thomas Wakley, the Victorian politician and reformer put it rather well: “The coroner was the people’s judge, the only judge the people had the power to appoint. The office has been specifically instituted for the protection of the people.” We erode the coroner’s ancient powers at our peril.

The author is a former criminal barrister. His debut crime novel The Coroner is published in January by Macmillan, £10

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