Peers have condemned the Independent Inquiry into Child Sexual Abuse's continued investigation into allegations against the late Lord Janner as an “affront to justice.”

Lord Janner, who died three years ago, was accused of child sex abuse offences but was never convicted of a crime.

The ex-MP, who was also President of the Board of Deputies from 1976 to 1984, died as the Inquiry was investigating claims against him, but a series of judges had ruled he was not fit to stand criminal trial.

In a debate in the House of Lords on Thursday, Lord Dale Campbell-Savours said the Inquiry continuing a dedicated investigative strand into Lord Janner, when he was not able to answer any claims against him, was an “affront to natural justice.”

He said: "I have a fundamental objection to the Inquiry’s management. It gives credence to hearsay and allows for the presumption of guilt in the court of public opinion.”

He insisted the Inquiry examine “only cases where guilt has been established in a court.

“Without due process the door is open to huge injustice and the trashing of reputations, and is an affront to every tenet of natural justice I have nurtured over a lifetime".

The Inquiry was set up to consider “whether and to what extent public bodies and other institutions have taken seriously their duty of care to protect children from sex abuse and seek to address public concern over failings exposed by appalling cases of organised and persistent child sexual abuse.”

Commenting on the Inquiry’s investigation into “Institutional responses to allegations concerning Lord Janner,” Lord Campbell-Savours said “justice had been stretched to breaking point”.

Lord Campbell-Savours, who has spoken previously criticising the Inquiry, said that the Inquiry regarded Lord Janner as “guilty until proven innocent.”

He said it was “tainted by the stench of injustice” because of a process where “behind the cloak of anonymity, unsubstantiated and unchallenged claims are made in open hearings”.

He claimed that “calculated dishonesty” was “at the heart of claims” against the late Labour peer.

During the debate, the Conservative Peer Lord Finkelstein said it was "very odd one" that the Inquiry would have a dedicated strand investigating Lord Janner.

He said the Inquiry should not think "because he is dead, it matters less what is said about him.

"He has a family who loved him and his reputation matters to his family. He belonged to a community and it much admired him.

"He was a parliamentarian and he thrived here. His reputation mattered to parliament and his reputation matters to me too."

Lord David Hunt also expressed concern that the Inquiry into Lord Janner would result in unproven allegations being placed in the public domain without cross-examination.

Lord Janner was a leading figure in Anglo-Jewry for more than 40 years. He was an MP from 1970 to 1997, when he was elevated to the House of Lords. He was known for his role in campaigns to win reparations for Holocaust victims.

His family have always maintained his innocence.

Lord Janner’s daughters, Marion Janner and Laura Janner-Klausner, Senior Rabbi to Reform Judaism, released a joint statement saying the “Inquiry’s current approach undermines its credibility".

They said: “Now that the full facts have been brought to light in the House of Lords, we call on the Inquiry to drop the immoral investigative strand into our father, who died an innocent man."

His son Daniel Janner QC has previously said: "The child abuse inquiry must now drop the strand in my innocent late father’s name."

In a statement, Manny Waks, chief executive of Kol v'Oz, an organisation dedicated to preventing child sexual abuse in the global Jewish community, said: "Just as we can't state unequivocally that the late Lord Janner is guilty of the serious and numerous crimes attributed to him, his family cannot possibly state as fact that he is an innocent man."

Those who have who have accused Lord Janner of sexually abusing them as children should be heard within the confines of the Independent Inquiry, he added. "If we are to progress as a society in the context of addressing the scourge of child sexual abuse, we must learn from the past. This includes making difficult decisions. It is understandable that Lord Janner's family are upset, but our primary goals in this case must be about justice and protecting current and future generations of our children.

"An 'affront to justice' is when victims don't get an opportunity to pursue justice - not when a person accused of unspeakable, countless crimes by numerous individuals is investigated after his passing."