A top civil servant and a senior member of the royal household have both been criticised in an official report examining attempts by a victim of child sex abuse to have his abuser stripped of an honour.

The Independent Inquiry into Child Sex Abuse recently found that Hubert Chesshyre – an acclaimed heraldry expert and a member of the Queen’s household – had been shown “preferential or exceptional treatment ... because of their status and contacts, regardless of the known involvement of child victims”. Jimmy Savile and Cyril Smith enjoyed similar leniency.

Chesshyre was made Commander of the Royal Victorian Order (CVO) in 2014, the year before he was charged and tried on a charge of sexual offences against a child.

He was by then suffering from dementia and found unfit to plead, but at a trial of the facts a jury agreed unanimously that he had committed two specimen counts of indecent assault against a child. A third charge was ordered to lie on file. Because Chesshyre had been found unfit to plead, no conviction ensued and he was granted an absolute discharge.

In October 2015, the victim, who provided a detailed witness statement to the inquiry about how Chesshyre groomed and abused him between the ages of 12 and 16, approached the honours and appointments secretariat at the Cabinet Office to ask how his honour could be rescinded.

He was told to contact Sir Alan Reid, keeper of the privy purse, as a CVO is the personal gift of the sovereign. But Reid, who has now retired, said that because Chesshyre was given an absolute discharge, “it would be wrong to submit a recommendation to the Queen”. Documents handed to the inquiry by Sir Jonathan Stephens, a senior civil servant who chairs the honours forfeiture committee, reveal that Reid received help in drafting his response from Thomas Woodcock, who is the Garter Principal King of Arms, the senior officer of the College of Arms, of which Chesshyre was a member for 40 years.

Reid asked Woodcock for some “suitable wording” to use in his response to the victim. On 4 November 2015, Woodcock wrote back to Reid enclosing a copy of a letter from Chesshyre’s solicitors containing their advice on the outcome of the trial of the facts. Reid thanked Woodcock “for providing the precise wording which I can use to answer [the victim’s] letter, and I have written to him today to this effect”. The inquiry judged that Reid’s response was “flawed and not impartial”.

A spokeswoman for Buckingham Palace said it did not comment on individual members of staff. “During an earlier review on the case, based on the facts that were presented, forfeiture was not recommended,” she said. “After this initial decision, we reviewed our processes, and changes were made to reflect lessons learned.”

After an intervention from the victim’s MP, Jim Dowd, the forfeiture committee recommended the Queen approve the removal of the honour. But the victim did not learn of this until five months after the decision. Stephens explained to the inquiry that this was because the forfeiture committee was considering “representations and new information provided to it by Chesshyre’s brother on his behalf”. The inquiry said that it was “regrettable that the Cabinet Office did not write to the victim during this period, at least to inform him that the process remained ongoing”.

The College of Arms, Queen Victoria Street, City of London. Photograph: Geoffrey Taunton/Alamy

The committee took the almost unprecedented decision not to publish the forfeiture in official journal of record the London Gazette. Stephens told the inquiry “that this was a reflection of how the case had been handled and, to a lesser degree, in light of Mr Chesshyre’s ill-health”.

The inquiry said neither reason was satisfactory. It also noted that Stephens had acknowledged that the failure to publish confirmation of the forfeiture had made it difficult for the victim to bring Chesshyre’s abuse to the attention of prestigious organisations of which he continued to be a member. “Most of those organisations have chosen not to cease their association with Chesshyre,” the inquiry said.

Chesshyre’s victim told the Observer: “I think that it is important that the IICSA has been able to consider evidence of the ways in which Mr Chesshyre used his position within the royal household to enable grooming and abuse. In light of the inquiry’s finding that there was not ‘a satisfactory explanation as to why an exception was made to the usual rule that forfeitures are published’, will the forfeiture now be published in the London Gazette?”

A government spokesman said: “The forfeiture process is confidential and it would be inappropriate to comment on individual cases.”