The decision not to prosecute the Labour peer Lord Janner over historic child sex abuse allegations will cause the public to consider any investigation into the establishment as a "whitewash", senior politicians have warned in an open letter.
The Crown Prosecution Service (CPS) last week confirmed Lord Greville Janner, 86, would not be charged with a string of historic sex offences against children due to the "severity" of his dementia.
He was diagnosed with Alzheimer's disease in 2009 and has been on a formal leave of absence since October 2014.
A cross-party group of politicians, co-ordinated by Labour's Simon Danczuk, claimed in a letter to The Times that the decision by the Director of Public Prosecutions Alison Saunders was "damaging public confidence" in the justice system and urged her to reconsider her decision.
The letter, co-signed by politicians including Conservatives Sarah Wollaston and Nadine Dorries, John Mann of the Labour Party, Ukip's Mark Reckless and Caroline Lucas, of the Green Party, asks: "Have we learnt anything from the mistakes of the past?"
"As long as justice is not seen to be done and the greater public interest is not served, the public will see attempts to investigate establishment figures involved in historic child abuse as a whitewash.
"The CPS has acknowledged the case against Lord Janner passes its evidential test, and there are established precedents in proceeding with cases against defendants with advanced dementia.
"Defendants have been charged with child abuse and found guilty in their absence. One man's ill health cannot be a barrier to the greater public interest."
In a statement condemning the decision not to prosecute Lord Janner, Leicestershire Police said there was credible evidence that he had committed “some of the most serious sexual crimes imaginable”. More than a dozen people came forward with claims of abuse relating to the former Leicester West MP.
The force said it is exploring any possible legal avenues to challenge the decision.
Lord Janner’s family issued a statement shortly after the decision not to prosecute him was announced, insisting he was “entirely innocent of any wrongdoing”.