A TOOWOOMBA man who suffered harrowing sexual abuse as a child is calling for an overhaul of the Royal Commission into Institutional Responses to Child Sexual Abuse.

The man, who is giving evidence for the criminal trial of his alleged abuser, gave evidence to the commission in Toowoomba last year.

He said he was raped as a primary school student in a Victorian school, which taught him to avoid notorious sexual predators at a Christian Brothers college.

With the focus of the commission on the Catholic church, and senior figures being named and shamed, the Toowoomba man said not enough focus was being put on public school victims.

"There is a lot of desperation, frustration and animosity out there among many victims of childhood sexual abuse perpetrated within the state system with many victims feeling snubbed and left with no confidence in either the proceedings, or that they will benefit from any future redress scheme," he said.

The man said many victims and their families have had their hopes for justice dashed by the "system".

"The system allowed the abuse to happen; the system accepted no responsibility for what happened; the system covered things up, and now the system ensures that no one is held accountable.

"Many victims from state schools, children's homes, orphanages and residential care feel they have been largely ignored by the commission and that the state is hiding under the robes of the church.

"It appears that our national and state governments are prepared to sit on their hands whilst the Catholic Church cops a roasting, so long as they themselves are not held accountable, responsible, or financially obligated to redress what those perpetrators working within the state systems did.''

He said the church was viewed as a bottomless pit of money and a much welcome diversion that freed the Australian and state governments of any moral or ethical responsibility.

The man first revealed details of his sexual assault in 2014.

Remembering the horrific details of the rape, which took place on a school outing, made him sick.

Soon afterwards police were informed and he later gave evidence to the commission.

A trial of his alleged abuser is under way in Victoria.

He said his assault gave him enough grounding to avoid the endemic abuse that was taking place at the college.

"On my first day at a well known Christian Brothers College the rumour mill was in overdrive. Watch out for brother so-and-so, he likes boys; so-and-so is gay, so keep your towel around you when you change," he said.

"Telling another teacher of anything was usually met with the standard response: 'uh, don't be ridiculous'.

"Worse still, was that until a few years ago, no one had any inkling that the school counsellor who every student put their trust in was a paedophile himself."

The man said his abuse had ruined his life, with people often calling him strange or unusual.

"You even question yourself sexually," he said.

But he's also drawn strength from his ordeal, and now assists other victims of abuse.