The Goddard Inquiry into historical child sex abuse has postponed its hearings on Lord Greville Janner until next March in part because of another probe into the way Leicestershire Police handled allegations against him.

It comes as lawyers for the former Labour peer’s family hit out at the Inquiry’s “wholly unfair” suggestion that a “finding of fact” may still be made, and argued that allegations against Janner should be excluded altogether.

“The role of the Inquiry is to investigate whether public bodies and other non-state institutions have taken seriously their duty of care to protect children from sexual abuse,” a family lawyer said. “Lord Janner was an individual not an institution.”

He added that a “finding of fact” would be “wholly unfair as Lord Janner is dead and there is no right to cross-examine witnesses on his behalf”.

The family’s reaction comes after the Inquiry postponement, which itself followed a decision by the Independent Police Complaints Commission to serve criminal and gross misconduct notices on 11 people over the alleged mishandling of complaints in April last year.

Janner, who had dementia, died last year aged 87, while awaiting a so-called trial of the facts based on 22 allegations of historical sexual offences against nine boys, many of whom were in care at the time.

He was subject to three police investigations between 1991 and 2007, but never charged. Commenting on suggestions that police officers undermined victims, retired High Court judge Sir Richard Henriques said it amounted to a “remarkable’ failure”.

Janner’s family have always insisted he is innocent of any wrongdoing, with the lawyer saying: “He was an honourable man, entirely innocent and never convicted of any crime.”