It was one of those real, not fake, “what a coincidence” moments. Last Saturday, Peter McClellan, chairman of the Royal Commission into Institutional Responses to Child Sexual Abuse, delivered a keynote address to the Australian and New Zealand Association of Psychotherapy in Sydney. The topic turned on child sexual assault and memory.

The NSW Court of Appeal judge was due to be introduced at the conference by Cathy Kezelman, president of the Blue Knot Foundation, which represents adult survivors of childhood sexual abuse. Kezelman’s own story is told in her book Innocence Revisited: A Tale in Parts (JoJo Publishing, 2010).

It so happened that the same day The Weekend Australian Magazine published an article by Richard Guilliatt titled “Through the past, darkly”, which raised questions about Kezelman’s alleged sexual assault by her father and others during her childhood. As it turned out, Kezelman was a late withdrawal from introducing McClellan at last Saturday’s conference, due to ill health.

Guilliatt quotes Claude Imhoff, Kezelman’s brother, as totally rejecting everything Kezelman says in Innocence Revisited about being assaulted by her father, who she alleges had the endorsement of her grandmother. Imhoff was emphatic, declaring: “It’s not that I don’t remember those things, I can categorically state that those events never happened.”

In other words, Imhoff is saying that his sister has a clear “recollection” of events that never occurred.

In a letter published in The Australian last Wednesday, Kezelman’s mother Lusia Puterman writes that she does “not believe that the events Cathy describes ever took place”. Puterman says that two decades ago “Cathy suffered a breakdown and began recovering repressed memories of sexual abuse by her father, grandmother and others”.

So here we have two sets of memories from within one family. A daughter, through a recovered memory, recalls terrible tales of sexual abuse by her father. And a mother and son state emphatically that no such events took place in the family home or elsewhere.

This would be a matter of no particular moment except for one fact. After all, it is not uncommon for siblings to have totally different, even contradictory, recollections of their childhood. Likewise one or more parents with respect to one or more offspring.

The problem is that Kezelman and her Blue Knot Foundation are much favoured by the royal commission. Indeed, McClellan is on record as describing Kezelman as an “old friend” of the commission. And she has been appointed to the commonwealth advisory council that will make decisions with ­respect to compensation and counselling following the report of the royal commission, which is scheduled to be handed down in December.

More significantly, the royal commission has accepted the counselling guidelines promoted by Kezelman and her Blue Knot Foundation concerning the recovery of what is termed repressed memory.

In short, Kezelman and her supporters are a significant part of the royal commission set up by the commonwealth, state and territory governments at a cost of more than $500 million.

Guilliatt reported in The Australian on Monday that McClellan has said he will not comment on the criticisms of Kezelman and her approach to counselling. But he should have a thoughtful take on this issue.

No one is alleging dishonesty in this case. Rather, the argument turns on memory, which happens to be central to the royal commission’s deliberations.

In a speech that he delivered in August 2006 (when a judge of the NSW Supreme Court), McClellan referred to “the fallibility of memory”. He commented on the “debate … as to whether repressed memories are reliable, or whether they are falsely induced by therapists”. And he concluded that “only rarely, if ever, will a person go to the grave with a clear and unaltered recollection of what happened yesterday, let alone of something that happened years before in their youth”.

In his address last Saturday, McClellan adopted a different tack. He argued that, with respect to child sexual assault, “victims … often find it difficult to provide adequate or accurate details in relation to the offending”. But he added that such circumstances were common and “do not indicate memory impairment or dishonesty”. Concerning the complaints of adults about sexual assault in their childhood, McClellan raised no doubts about the recovered memory process.

The royal commission chairman also appears to have undergone a metamorphosis concern­ing juries. In an address to the University of NSW’s law faculty in December 2011, he was reported to have said that some trials were too complex for juries and they made poor decisions. While on the NSW Court of Appeal, he was involved in overturning some convictions in the criminal jurisdiction. The message appeared to be that juries too often convict the innocent.

However, in a speech to the Modern Prosecutor Conference in Melbourne last April, McClellan criticised the fact while the number of complainants alleging child sexual abuse has increased, conviction rates have fallen. The message appeared to be that juries too often acquit the guilty.

Australians are entitled to know the extent of the relationship between the royal commission staff and the Blue Knot Foundation with respect to recovered memory and the like, not least because Kezelman will be involved in the distribution of up to $150,000 to every complainant who is accepted as a victim of child sexual abuse following the report of the royal commission.

Meanwhile, in Britain, police in Wiltshire have reported this week on their investigation into historic child sexual abuse offences allegedly committed by Edward Heath (1916-2005). The inquiry, which cost £1.5 million, was unable to corroborate any claims made against the former prime minister.

Only seven out of about 40 witnesses who gave evidence to the inquiry were deemed credible or gave accounts that could not be disproved. One complainant, “Nick”, is reportedly a complete fantasist who may be charged for making false claims. The remaining seven cases, which cannot be disproved or proved, turn on the recall of events that allegedly took place decades ago. Once upon a time, the royal commission chairman would have warned about the fallibility of memory in such cases.

Gerard Henderson is executive director of the Sydney Institute. His Media Watch Dog blog can be found at www.theaustralian.com.au.