The commission is investigating abuse in state and faith-based care between 1950 and 1999 and is currently hearing the experiences of survivors in seeking redress, such as compensation, counselling or an apology.
Speaking from prison via AVL, Johnson said he was taken out of his mother's care by Social Welfare and placed in Marylands aged 7 due to being an "out of control kid".
After his time at Marylands, he was taken to Campbell Park School in North Otago in March, 1981, where he remained for 6 years.
His time there was "my nightmare", he said.
"They didn't just rape you, they beat the living daylight out of you."
He spoke of being kicked, hit and beaten with planks of wood, and made to stand outside naked in the cold.
He spoke of having to comfort boys, "fresh" ones, who'd just been raped by staff.
"I could hear boys screaming at night while they were being sexually abused."
Some of those friends didn't make it.
"They had no one. I still have nightmares [about finding them]."
He started to hurt himself around this time, and had trouble sleeping, and wetting the bed as he was "too scared" to go to the bathroom in the night.
He wasn't under care of social welfare at this time, but near the end of Campbell Park he became a ward of the state.
He also started to become violent, getting in fights with other boys.
In 1987 he was admitted to Stanmore Road, a boys' home in Christchurch.
"When I first got there, I attacked the first boy I saw. I beat him up, then they stuck me in the secure unit. I spent most of my life, most of my time in the secure unit, because I was a violent boy, I was attacking every person, even staff. I was attacking them."
Asked why by his counsel Sonja Cooper, Johnson responded: "Because I didn't want anyone to touch me no more."
He also spent short periods of time at Kingslea Boys' Home, and Templeton Hospital and Sunnyside Hospital.
The impacts of the abuse had been wide-ranging.
"It's been a hard life for me. They took my childhood away from me.
"I've been in and out of jail since then. That's all I've known. That's all my life has been. I've lived a gang life.
"I used to run with gangs because I thought that was my family. I trusted them more than anything else… I became a criminal because that's all I've known.
"I didn't know what wrongs a right was, I just did what I had to do to survive."
He told the commission since his teenage years the longest stint he's had out of jail has been one year.
In 2004 he got in touch with Sonja Cooper at Cooper Legal, and thus begun his process of making claims against the Ministry of Social Development, Ministry of Education, and SJOG.
In 2007 he received a settlement of $28,500 from SJOG, and a top up a little over 10 years later of another $25,000, to balance it with other claims being made against the order.
He received $5000 from MSD, which he was advised not to take, but he accepted as he "wanted it to be over".
He also received a letter of apology from then-chief executive Brendan Boyle.
But 16 years after starting his claim for the abuse at Campbell Park, Johnson is still fighting for recognition from the Ministry of Education.
"I can't understand why my claim still hasn't ended, after all that time.
"My experiences in care, and the journey I have had to take to resolve my claims, have been a nightmare.
"I feel like my life is stuffed and that I'm stuck in a horror movie that will never end.
"It feels like the Government just wants to sweep this all under the carpet and that it doesn't want to hear any of it.
"It is hard for me to confront all this. Even so, I am providing this evidence because I know that I need to speak up for myself, and for my mates who didn't make it.
"It's time that the Government finally owned up to what happened to us while we were in care. There isn't any chance of me being able to move on and put this all behind me, until that happens."
Cooper asked Johnson if any of the processes of support and rehabilitation had helped him to recognise his Māori identity.
"Not at all," he said.
"I never learned my whakapapa. I wish I did, so I could understand my Māori side.
"When I get out this time my aim is to go see my father, I want him to teach me my whakapapa."
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