Allegations: Veteran peer Lord Janner (pictured in 2002) has repeatedly denied claims he abused young boys at care homes and is now not fit to stand trial despite 'credible evidence'

Lord Janner should have been charged with historic child sex offences on three occasions over 25 years and will now never be prosecuted because of the 'severity' of his dementia, the Crown Prosecution Service said today.

Alison Saunders, Director of Public Prosecutions, has expressed her 'deep regret' that the 86-year-old former Labour MP for Leicester West will not face trial because of botched investigations in 1991, 2002 and 2007.

The decision not to charge him with 22 alleged sex attacks on children has infuriated police and campaigners, who have called it 'perverse' and a 'step backwards for justice'.

Leicestershire Police may appeal because they handed the CPS 'credible evidence', including videos, showing 'this man carried out some of the most serious sexual crimes imaginable'.

Sir Clive Loader, the Conservative Police and Crime Commissioner for Leicestershire, said: 'This decision is not just wrong - it is wholly perverse and is contrary to any notion of natural justice. I cannot believe that any right-minded person will understand or support it'.

Labour has now suspended the veteran peer from the party 'in light of these very serious allegations'.

While one alleged victim branded the decision not to pursue the case 'a disgrace', Lord Janner's family said he is 'entirely innocent of any wrongdoing' and 'is a man of great integrity'.

More than a dozen people came forward to claim Lord Janner abused them during the 1960s, 1970s and 1980s, the CPS said.

Today they admitted there is enough evidence to prosecute the peer for 16 indecent assaults and six counts of buggery, but he is no longer fit to stand trial.

Mrs Saunders said: 'The CPS judges that mistakes were made in the decision making at the time by both the Leicestershire police and the CPS. Lord Janner should have been prosecuted in relation to those complaints. It is a matter of deep regret that the decisions in relation to the previous investigations were as they were'.

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Pointing: Channel 4 News filmed Lord Jenner outside his house in London on July 8 2014, in what was is the most recent moving image of the Labour peer

She said Lord Janner may have 'befriended the manager of a children's care home to allow him access to children in order to allow him to perpetrate serious sexual offences on children'.

But almost 25 years after he was first investigated poor health means the CPS has decided to not pursue the case in the courts.

Mrs Saunders said: 'The CPS has concluded that Lord Greville Janner should not be prosecuted because of the severity of his dementia which means he is not fit to take part in any proceedings.

'There is no treatment for his condition, and there is no current or future risk of offending. But for medical considerations, it would undoubtedly have been in the public interest to prosecute'.

Lord Janner attended the House of Lords 15 times in November 2013 and 12 times in December 2013. Police searched his home on December 20, 2013 and he has not attended Parliament since.

He last took part in a vote on November 26, 2013, on the Financial Services (Banking Reform) Bill.

Director of Public Prosecutions: Last year, Alison Saunders (pictured) said prosecutors will pursue justice for victims of child sex crimes whether their cases were '30 days or 30 years old' - but not in the Janner case

Detectives have interviewed more than 20 men who claim they were abused, but have been unable to speak to Lord Janner because of his poor health.

In a statement issued through lawyers, the peer's family said: 'Lord Janner is a man of great integrity and high repute with a long and unblemished record of public service. He is entirely innocent of any wrongdoing.

CPS REJECTED THREE EARLIER CHANCES TO PROSECUTE JANNER 1991: A complaint of sexual assaults by one individual who featured in the trial of paedophile care worker Frank Beck. The allegation, in essence, was one of grooming and sexual abuse of the alleged male victim between the ages of 13 and 15. The CPS decided there was insufficient evidence to prosecute. 2002: In an investigation named Operation Magnolia. Lord Janner was the subject of allegations as part of a probe into abuse children's home. The CPS says specific allegations relating to him were not referred to them and claim police chose not to pursue him. 2006: As part of a new sex abuse investigation, Operation Dauntless, an alleged victim made allegations of serious sexual offending around 1981 by three individuals including Lord Janner. The CPS decision in 2007 was again that there was insufficient evidence to prosecute. Advertisement

'As the Crown Prosecution Service indicated today, this decision does not mean or imply that any of the allegations that have been made are established or that Lord Janner is guilty of any offence.'

Following the CPS announcement Labour said it had suspended him from the party.

Leicestershire Police said they are 'exploring what possible legal avenues there may be to challenge' the decision by the CPS. The force says it has seized cine film and video evidence that could be used to prosecute the peer - and says the CPS' decision is the 'wrong one'.

The force's assistant chief constable Roger Bannister, who has overseen the investigation, said: 'There is credible evidence that this man carried out some of the most serious sexual crimes imaginable over three decades against children who were highly vulnerable and the majority of whom were in care.

'I am extremely worried about the impact the decision not to prosecute him will have on those people, and more widely I am worried about the message this decision sends out to others , both past and present, who have suffered and are suffering sexual abuse.

'We are exploring what possible legal avenues there may be to challenge this decision and victims themselves have a right to review under a CPS procedure.'

Probes: Greville Janner, left in 1974, served as an MP for decades and was investigated in 1991, 2002 and 2007. Janner was mentioned during the trial of paediophile Frank Beck, right, who died in jail

The investigation, codenamed Operation Enamel, traced 25 people who allege that they were sexually abused by him.

ALLEGED JANNER VICTIM FUMES OVER 'DISGRACEFUL' DECISION A man who claims he was abused by Lord Janner branded the decision not to pursue the case ‘a disgrace’ and accused prosecutors of protecting the politician because of his status. In an angry statement released via Leicestershire Police, the alleged victim told of the ‘pain and suffering’ he claims to have suffered. And he says the peer should stand trial so alleged victims have an opportunity to have their day in court. The man, who is not named, said Lord Janner is ‘being protected’ and today’s announcement is ‘not in the public interest’. He said: ‘If he was an everyday person with a normal life and job, justice would [have] been served.’ He said the peer’s alleged victims are ‘just being pushed to the ground again and walked over. ‘Let someone feel the pain and suffering that I’ve endured and still going to endure for the rest of my life. It’s not a case of being found guilty or going to prison - it’s about being believed after so long being told that we were lying. Justice needs to be served.’ The man is one of 25 people who claim to have been assaulted in Leicestershire between the 1960s and 1980s by Lord Janner. Advertisement

The CPS has spoken to all of them ahead of the announcement to tell them he will not face trial.

Lord Janner was diagnosed with Alzheimer's disease in 2009 and requires round-the-clock care.

The CPS said that 'but for medical considerations, it would undoubtedly have been in the public interest to prosecute' and the peer would be facing trial.

But because of his condition, which affects the memory, Lord Jenner is not fit to plead or give evidence, and therefore a criminal trial 'could not now properly take place'.

Lord Janner's alleged victims have been old about the decision, and have said they want to tell their stories publicly.

Mrs Saunders said: 'The lack of a prosecution will be extremely disappointing to complainants. I have written to each of them, explaining the reasons for the decision, inviting them to a meeting with me so that I can explain any matters to them further, should they wish.'

Leicestershire Police said in a statement: 'During the course of the investigation, more than 2,000 individuals were seen and 442 statements taken. Detectives pursued more than 2,700 lines of enquiry, and seized/created nearly 600 exhibits including cine film and videos.'

The controversial decision will spark fury among his alleged victims and child abuse campaigners who will see it as a landmark climbdown.

Last year, Mrs Saunders said prosecutors will pursue justice for victims of child sex crimes whether their cases were '30 days or 30 years old'.

She is already under huge pressure amid criticism of high-profile prosecutions of journalists accused of illegally paying public officials for information.

Influential: Lord Janner was chair of the Holocaust Educational Trust and vice-president of the World Jewish Congress

Lord Janner has avoided prosecution before after a bungled Leicestershire Police inquiry between 1989 and 1991.

Royal: Queen Elizabeth II and Lord Janner in 2003

He was interviewed at a police station but senior officers told detectives not to arrest him or search his properties.

Police visited alleged victims of Lord Janner yesterday evening to inform them of the decision.

Senior figures at Leicestershire Police are unhappy with the decision, with one describing it as 'perverse'.

Some believe there is enough evidence for a 'trial of the facts' in Lord Janner's absence which would settle the matter once and for all. The long-running Leicestershire Police inquiry, codenamed Operation Enamel, will continue as it has identified other suspects.

Pete Saunders of the National Association of People Abused in Childhood, said the decision was a 'step backwards for justice'.

'There is enough evidence to proceed with the case and for Alison Saunders to say it is not in the public interest is an outrage,' he said. 'I am not saying it is in the public interest to send a very old man to prison, but surely it is in the public interest to expose the evidence and give victims the chance to be heard.

'The message here is that if you are old or important you can still get away with it.'

Meanwhile spoon-bending magician Uri Geller has claimed his friend Lord Janner could not stand trial because 'the man's mind is out, finished, totally erased'.

He first met the peer around 30 years ago and the pair were photographed together with singer Michael Jackson on a tour of Parliament in 2002.

This decision is not just wrong - it is wholly perverse and is contrary to any notion of natural justice Sir Clive Loader, Police and Crime Commissioner for Leicestershire

But he claims that Lord Janner no longer recognises his own family, and did not know who he was three years ago.

Despite his illness the peer voted on 37 bills in the House of Lords in 2013 - but none since then.

Mr Geller said: 'Greville has been suffering from increasing dementia. The last time I saw him was about three years ago and I was utterly shocked that he didn't recognise me or the guests I'd brought along.

'Although my own son works for the Crown Prosecution Service, I'm not a barrister or a lawyer and in my opinion the question that has to be asked here is how can a man whose mind has been totally erased, how can such a person defend himself in court?'

Leicestershire Police have amassed a huge dossier of information during their investigation into claims about Lord Janner. This has led to warrants being obtained to search his home in north London and his office in the House of Lords.

Other case: Lord Janner (pictured in 2000) has avoided prosecution before after a bungled Leicestershire Police inquiry between 1989 and 1991

The claims against him first surfaced during an investigation into Frank Beck, a manager of Leicester children's homes who died in jail after being convicted of abusing boys in his care.

A former resident of one home alleged he had a two-year sexual relationship with the MP when he was a teenager in the 1970s.

The alleged victim later caused controversy when he aired the allegations in public while giving evidence at Beck's trial in 1991.

MPs on all sides rallied around Lord Janner when he told the House of Commons the claims did not contain a 'shred of truth'.

But a former Leicestershire detective, now a leading chief constable, said senior officers blocked the probe.

Mick Creedon, who now runs Derbyshire Police, said he was ordered to limit his inquiries into Lord Janner despite 'credible evidence' against him. Last year, he said a decision made 'by people more senior than me' led to an inadequate police inquiry.

The 1989-91 inquiry was limited to an interview at Leicestershire Police HQ during which Lord Janner gave 'no comment' answers. A file was sent to the CPS, which decided there was insufficient evidence to bring charges.

When the allegations became public during Beck's trial, the jury was told they were a 'red herring' and irrelevant.