The CPS has decided not to prosecute Lord Janner (pictured) over alleged child sex offences

There was a time when I regarded the idea of an ‘Establishment cover-up’ with a pinch of salt. Was it really plausible that the powers-that-be should act in concert over a prolonged period of time to suppress the truth?

Even if they attempted to do so, surely some decent person would sooner or later speak out, or inform the Press. It seemed unlikely that evil on a vast scale could be concealed more or less indefinitely in what is supposed to be a free and open society.

I’m afraid a succession of sex abuse cases have blown apart my preconceptions. It’s plain beyond any dispute that politicians, senior policemen and members of the security services have conspired to protect abusers because they were considered important, and to deny their victims justice.

Disturbing

First there was the almost inconceivable abuse carried out over a period of 50 years by the loathsome Jimmy Savile, notwithstanding several police investigations. Then there were the no less grotesque sexual assaults committed by the gargantuan Liberal MP Cyril Smith with the apparent indulgence of the authorities.

And now there is the equally disturbing case of Greville Janner — Lord Janner — a former Labour MP and one-time President of the Board of Deputies of British Jews, who has campaigned tirelessly, and most creditably, on behalf of Jewish victims of the Holocaust.

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But this pillar of the community, and apparently admirable man, is also alleged to be a paedophile, and stands accused of 22 sexual offences, said to have taken place from 1969 to 1998, involving nine children and young adults. These range from indecent assault to buggery.

So says the Crown Prosecution Service, which regrets it can’t bring a case against 86-year-old Janner as he is suffering from dementia. This hasn’t prevented him from attending the House of Lords hundreds of times since the diagnosis was first made in 2009, his most recent attendance being little more than a year ago. Nor has he been deterred from claiming more than £100,000 in parliamentary expenses and allowances during this period.

The decision by director of public prosecutions, Alison Saunders (left), has been criticised. Former Labour MP Margaret Moran (right) being deemed unfit to plead did not stop her being found guilty of forgery in 2012

Indeed, Janner signed a letter saying that he wanted to remain a peer just a week before he was judged unfit to face child sex charges. Either his dementia is not as severe as it is said to be — or someone induced him to sign a letter he could not understand.

The decision by Alison Saunders, the director of public prosecutions, is just the latest in a long series of institutional betrayals involving Janner. Even if he is incapable of defending himself, there is a legal precedent for establishing what took place called the ‘finding of fact’.

After all, in 2012 the former Labour MP Margaret Moran was found guilty by a jury of false accounting and six charges of forgery, despite having been absent from court because she had been deemed by psychiatrists to be unfit to plead.

And, in a case with striking similarities to Janner’s, five years ago at Exeter crown court Michael Collingwood, also suffering from dementia, was found to have ‘done the act charged’ when a case of the sexual abuse of under-age girls was heard in his absence.

It must be stressed that Lord Janner could be blameless of the charges against him. Innocent until proved guilty is a vital precept of English law. As it is, he has been deprived of the opportunity to salvage his good name by the CPS’s decision to avoid any kind of hearing.

Meanwhile, his alleged victims will never be able to see justice done, or to see their persecutor made to answer for his supposed crimes. One of them, Hamish Baillie, 47, has waived his right to anonymity, and given an account of being molested by Janner when he was a 15-year-old resident of a children’s home.

Labour MP Keith Vaz and others have unthinkingly assumed Janner was innocent

But however indefensible the CPS’s decision, it’s not the worst thing that has happened. Alison Saunders herself admitted Janner should have been charged in 1991, after allegations were made against him in a court case. Paul Winston, then aged 30, claimed under oath that the MP had abused him repeatedly between the ages of 13 and 15.

In other words, the Establishment closed ranks, with MPs of all parties expressing incredulity that Janner could be guilty of such terrible abuse.

According to Alison Saunders, there were two further missed opportunities in 2002 and 2007 when ‘the evidential test was passed’, which means there was a realistic chance of a conviction. No explanation has been offered by her or anyone else for this failure.

Labour MP Keith Vaz, the somewhat self-important chairman of the Commons home affairs select committee, declared in 1991 that his close friend and colleague Janner had been the ‘victim of a cowardly and wicked attack’.

Then Tony Blair breezily swept aside the serious allegations that had swirled around Janner by conferring a life peerage on him shortly after Labour won the 1997 election. The alleged abuser had been invited into the Establishment’s inner sanctum.

Blair, Vaz and others unthinkingly assumed Janner was innocent. They were unable to conceive that such a man could be guilty of the horrendous abuse of children. In short, they were lazily unprepared to confront the possibility of evil.

Sinister

But there is evidence that something more sinister was going on — that there was a deliberate Establishment cover-up. Mike Creedon, currently chief constable of Derbyshire, revealed last year that as a young officer in 1989 he was ordered by his superiors not to arrest Lord Janner or to search his home.

Alison Saunders has appointed a retired High Court judge, Sir Richard Henriques, to investigate the failure to bring charges against Janner. I wonder how far he will get in investigating these perilous and murky waters.

What is so depressing about this case is that it’s all part of a familiar pattern. Investigating police officers build a convincing case, but no proceedings are brought because the suspect is thought to be a good chap — or too powerful and important for charges to be brought against him.

There are parallels with Janner's case to those of Cyril Smith (right) and Jimmy Savile. Crucial intelligence on the sex crimes of Saville (left) is said to have been buried as long ago as 1964 because he was a celebrity

So it was with Cyril Smith. The parallels are eerily similar. As far back as the 1950s, police had their suspicions about the then Rochdale town councillor. But in 1976, inquiries were thwarted by Special Branch. All files on Smith held at police headquarters in Preston were allegedly removed by MI5 officers.

Last month, Albert Laugharne, a former Chief Constable of Lancashire Police, disclosed that in the 1970s he was asked to lie about Smith’s alleged sexual abuse of a young boy.

As far as Jimmy Savile is concerned, according to an official inquiry, crucial intelligence about his sex crimes was buried by the Metropolitan Police as long ago as 1964 because he was a celebrity. Police in Surrey and Sussex failed to follow up allegations against him in 2007 and 2008, by which time he was widely known as a chum of everyone from Prince Charles to Margaret Thatcher.

Betrayal

In all these cases, there has been a monumental betrayal of victims and a denial of justice. These appear to arise not merely from an assumption that the suspect is ‘one of us’, but also from the dark and collusive hand of the authorities.

In all these cases, there has been a monumental betrayal of victims and a denial of justice

How telling that the first two people appointed to head a new inquiry into historical sex abuse in England and Wales were classic Establishment figures. Both had to stand down because of personal connections to politicians who had been linked to the cover-up of sexual abuse in the Eighties.

It’s true the New Zealand High Court judge Lowell Goddard has now been named as head of the inquiry. I wish her all the luck in the world, but the scope of her investigations is too large, and it’s reasonable to wonder how far she will get.