In late 2019, Mr G made a complaint to the National Office for Professional Standards after seeing a newspaper article which named his abuser - Brother John Michael "Fabian" O'Driscoll - as a serious offender who had been the subject of multiple complaints.
He told the inquiry this month that when he was in Form 2, or about 12 years old, he was asked to come into the office of O'Driscoll, who was the principal.
A self-described "meek, mild, timid, compliant" kid, Mr G was unsure why he was being singled out when he had done nothing wrong.
Once in O'Driscoll's office, he was asked to lie across the principal's knees, and was indecently assaulted, Mr G told the inquiry.
"When I got to his office, he called me in, closed the door and said words to the effect, 'I am going to give you a massage'.
"Brother Fabian sat on an armless chair and told me to lay across his knees. I was wearing white sports shorts and a white singlet.
"As soon as I lay down, he put one of his hands down the back of his shorts under my underpants ..."
O'Driscoll, who passed away in 2006, was also his Form 2 teacher as well as his boxing coach and cricket coach, the inquiry heard.
"It seemed to go on for an eternity although it probably only continued for a few minutes," Mr G said.
"He then pulled his hand out of my shorts and told me to go back to training. He said nothing further."
Mr G didn't tell anyone about the abuse as he thought no one would believe him and his mother was heavily involved in school activities and thought she wouldn't believe him either.
"I was not prone to telling lies but at the time it was probably unthinkable that a Marist Brother would be capable of such behaviour."
Mr G said O'Driscoll continued to teach and coach him.
"He never, ever mentioned what he'd done to me, it was like it never happened. I started to question whether the incident had taken place, although it definitely had, and hoped my memory of what occurred would go away."
Mr G told the inquiry he didn't know of any other boys who were abused at Marist Brothers' School until the last two or three years, when he brought up O'Driscoll to his brother, signalling his intent to register a complaint with the commission.
His brother told him he had been abused by the previous principal Brother Benedict, who would abuse him while he was standing behind the lectern out of view of other boys.
He was told the same thing had happened to others, but was not given any names.
"This is an appalling state of affairs," he said.
"My classmates and I didn't deserve, nor did the Whanganui Catholic community who sent their children or boys to those schools, to have paedophile priests or brothers as principals. To me as a young person at those schools, those principals were God-like figures."
Mr G said that in hindsight the abuse he suffered impacted him more than he realised at the time, contributing to him losing his voice as well as affecting his first marriage.
"At primary school, I was one of the top three or four students in my class. However, following the assault, I found it significantly more difficult to learn and study."
In the 1980s, Mr G's voice began to deteriorate and change, to the extent he decided to leave his government job.
"I have seen many specialists, attended voice therapy and had operations but nothing has been able to fix the issue. I have now struggled with these voice issues for 33 years and spent a considerable amount of money attempting to restore the voice to what it was but it was unsuccessful, to be honest."
While he said he couldn't definitely say it was the actions from O'Driscoll that directly caused his voice issues, he believed the assault contributed at the very least and want an ex-gratia payment to cover some of the money he has spent on treatment for his voice.
Mr G also wants a written apology from the Marist Brothers acknowledging the conduct of O'Driscoll and the wider issue of abuse within the Marist Order.
He told the inquiry he had heard nothing from the Marist Brothers and thought the communication throughout the process could have been better.
"I think it has been slowed down by Covid obviously but I think the wheels have turned, the wheels of justice, for want of a better word, have turned quite slowly, to be honest."
When asked what the Catholic Church needed to do better when acknowledging past abuse, Mr G said it needed to be more vocal about what had happened and supportive of people who had suffered abuse.
Mr G said that following the completion of this Commission of Inquiry, he would like to see the implementation of an independent and impartial agency to deal with state- or religious-based organisations abusing people in their care.
Having such an agency would ensure all persons are dealt with in an equitable manner. This would eliminate victims of such abuse being treated differently in many ways, depending on which organisation the abuse occurred within, he said.
"That would allow benchmarks to be set and eliminate the necessity for victims having to negotiate and having ongoing dealings with the organisations ultimately responsible for their abuse."
Phase one of the hearing wraps up on Friday. In March, phase two will focus on evidence on redress processes from witnesses called on behalf of the Catholic Church in Aotearoa New Zealand, Anglican Church in Aotearoa, New Zealand and Polynesia and the Salvation Army New Zealand.
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