It would only take one conversation with police to yank the ground from under his feet, sending him spiralling down into drugs, despair, and renewed disbelief, and allowing his abuser to dodge justice for another decade.

Mr Farr was sexually abused in horrific circumstances for years by his former Scout master and a close friend of his parents, Willem Bowen Scheeren, 58, while growing up in Canberra.

His torment was so great, that he began to question himself and the truth of the abuse he suffered, including at Scheeren's Canberra shoe shop and in his own home.

"For a lot of the time I thought this is not real, this is not happening," he said.

"It's a way of coping with it."

Mr Farr worked up the courage to come forward to police 20 years later, when something happened to confirm the truth of the surreal memories haunting his mind.

He called Scheeren to secure a confession while police secretly listened in, and his abuser later admitted his crimes when interviewed by detectives.

But a problem emerged just as Mr Farr was on the cusp of seeing Scheeren's day in court.

An archaic legal loophole meant Scheeren could not be prosecuted because the charges had not been brought within 12 months of the crime. The law required female child sex victims, aged 14 and 15 between 1951 and 1985, and male victims between 1976 and 1985 to report crimes within the 12 months statute of limitations.

The old law was at odds with much that is now known about victims, and the many reasons that prevent them from coming forward early.

It was news that Mr Farr described as "bone-jarring".

"That really sunk me to new depths, let me tell you, I've never felt that low in my whole life," he said.

Scheeren has now been jailed – serving eight years – after retrospective reforms were introduced by the ACT government last year, closing the loophole and allowing the prosecution of such offenders.

Mr Farr knows there are other victims out there.

"I'm not a believer in closure, what this has done for me is it's provided justice," he said.

"I still have nightmares today, the same nightmare that I've had when I was eight years old from this happening. That doesn't go away just because he's gone to jail, you can't stop that part of it.

"I want other people to know that yeah it's still a hard journey, but it does give you a feeling of justice.

"Now it's all real. It wasn't just made up"

Now, Mr Farr is back in stable employment at a mechanic in Queanbeyan, where he is a business manager.

He has room to hope that he can move on with his life.

But he says what Scheeren did to him has irrevocably changed him.

"I don't know who I should have been, all I know is who I am now," he said.

"He's permanently changed that tangent for me."

Anyone with information should contact ACT Policing operations on 131 444.