Tihema Galvin is now a different man.
He was just 19 when he joined the Mongrel Mob, and he went to prison for the first time a year later.
"For many gang members, going to prison is fun," he said.
"Because it's only a little lag, you go in there, get fit, have a break from the drugs and alcohol."
Galvin was sentenced to jail for 12 years in 1992 for his involvement in a gang rape. During this time, things started changing for him. But it wasn't the longer sentence making the difference.
He was introduced to Mahi Tahi, a Māori rehabilitation program, meaning 'working together to share knowledge.'
"I put in a transfer to go to another prison. I got told 'your transfer's gonna wait, you might as well do this Māori wananga programme'. I had no interest in Māori things back then.
"Four guys came in and spent the whole week with us. They taught us what it meant to be Māori and what our tupuna were like. They taught us about our identity and things I knew nothing about before. The curtain was opened up for me."
Galvin now works for the prison programme which saved him.
Mahi Tahi's vision was simple, get Māori out of jail by reconnecting them with their roots.
"Some of these programmes are like putting on a plaster but these brothers need stitches. They need to be stitched up. And learning about their identity and tikanga - those are the stitches."
More than half of New Zealand's prisoners were Māori and Galvin says prison was, conincidentally, the perfect place to teach them about their culture.
"Tell me where else you're gonna get 15 guys from different areas and gangs in a marae together out here? You can't."
Galvin worked with inmates, gangs and whānau in Hawke's Bay, Te Awamutu and Palmerston North.
"I've seen a lot of success. A lot of the guys have not returned to prison. The ones we are working with now are the younger ones … that's where the challenge is."
Galvin himself was now a family man and his new life motivated him to help those still in need.
"People say to me 'you've done really well and congratulations' but it's really not what about what people think.
"I just care about opening up a curtain for the bros inside ... the same curtain that was opened up for me in 1996.
"I believe the only thing that's going to help Māori in prisons today is learning about their identity, learning about why we are Māori and where we come from."