The former Queensland DPP says she should never have shown legal advice to the alleged sex abuse victim of Scott Volkers.

A former Queensland Director of Public Prosecutions says mistakes were made in how her department handled criminal charges against swim coach Scott Volkers.

Now a judge, Leanne Clare has also told a royal commission she should never have shown an alleged victim of child abuse legal advice which argued authorities not revisit charges against Volkers in 2004.

Over the past five days the commission has focused on a 2004 letter from NSW Crown Prosecutor Margaret Cunneen to the Queensland DPP advising not to recharge Volkers due to a lack of evidence.

The advice centred on the likelihood of physical aspects of the attacks occurring, including the abuse happening through three layers of clothing.

Judge Clare subsequently showed the advice to one of Volkers alleged victims, Julie Gilbert.

“I shouldn’t have done that,” she told the Royal Commission into Institutional Responses to Child Sexual Abuse on Wednesday.

The commission is investigating how swimming and government authorities handled the allegations against Volkers.

At the start of the hearings last week Ms Gilbert told the commission she was appalled by the advice when she saw it – in particular parts of it which questioned whether 12-year-old girls have breasts and the likelihood of sexually abusing a child through layers of clothing.

Judge Clare told the commission she did not rely on Ms Cunneen’s advice to drop the charges, but nevertheless regretted showing it to Ms Gilbert.

Judge Clare said she accepts mistakes were made in the handling of the original 2002 case, and accepted as valid criticism levelled against her former department in 2003 by the crime and misconduct commission (CMC).

The CMC investigated the circumstances surrounding the Queensland DPP’s decision to charge Volkers with sexual assault offences against three women dating back to the 1980s.

By the end of 2002 the charges were dropped.

The CMC report found there were more defects than one would normally expect in handling the case, and the process that led to the dropping of the charges was unsatisfactory.

It also said then Deputy DPP Paul Rutledge and to a lesser extent Judge Clare could be justly criticised over how they performed their tasks.

However, the matter fell short of official misconduct, the CMC report said.

“I accept that criticism about the way which the matter was handled was valid,” Judge Clare said.

“There were mistakes made clearly in that case. But I did not agree with some of the conclusions of the CMC in relation to the decision itself, the merits.”

Throughout Wednesday’s hearing Judge Clare said she stood by her decision because there was not enough evidence to convict Volkers.

Judge Clare also told the commission that when stacked up, the allegations against Volkers were substantial.

But she defended her decision not to pursue the charges.

“I have not doubted that that was the right decision at that time,” she said.

“It was a reasonable assessment of the climate in which we were working back in 2002.”