The family of Greville Janner wants the public inquiry into child abuse to delay its investigation into the late Labour peer.
Lord Janner, 87, who died in December, is alleged to have abused youngsters over a period spanning more than 30 years dating back to the 1950s, with offending said to have taken place at children's homes and hotels.
The allegations against him are due to be examined at hearings of the public inquiry next March.
But his son has said that as civil proceedings by some of his alleged victims have been started, the claims should go through the courts - where his father's accusers can be cross-examined - before they feature in the inquiry.
Daniel Janner QC told the BBC he had prepared a submission for the Home Affairs Select Committee which is due to question Home Secretary Amber Rudd next month.
He said: "We very much hope that the committee will question carefully why the inquiry is planning to make findings of fact in relation to my late father when he is dead, when he cannot answer back, when he has never been convicted of any offence and is entirely innocent.
"Moreover we are denied the right to cross-examine what we know to be false allegations and we say this process actually discredits the important work of the inquiry.
"Civil proceedings are in train and it is in those civil proceedings that we do get the right to cross-examine, when those allegations can be tested."
He said he and his two sisters intended to use their inheritance to clear the family name.