Tom Marsh was just 12 when he had his first brush with the law after he assaulted a teacher, and has been in jail four times for offences ranging from robbery to drugs.
Growing up, Marsh, 26, from South Auckland, says he knew nothing other than a life of crime.
But within a space of seven months, he has turned his life around from being a criminal and drug addict to become a supervisor at work and a role model - all because of a promise he made to his dying mother.
When Marsh came out of prison for the fourth time in May, he didn't know his mother was suffering from advanced cancer.
"Mum said she wanted to talk to me, and I thought it'd be one of her usual lectures," he said.
"But she just held my hands said she loved me, and said 'son, promise me you won't go back to jail'."
Marsh said those were her last words to him, and the next day she died, aged 46.
"I didn't know she was dying, so it hit me real hard. Mum had it tough raising me and my brother by herself," he said.
"The very least I could do to repay everything that she has done is to honour her last words, and my promise."
Marsh signed up for a Skills Update Preparation for Work course, even though he didn't really expect to get a job out of it.
"With my criminal record, I thought who would even employ me or give me a chance," he said.
Determined to increase his chances, Marsh stopped smoking cannabis soon after starting the course so he could pass a drugs test.
Then Skills Update employment placement specialist Della Pope found a company, Trenchmate, a trenching company in Papakura willing to take Marsh on.
He was offered a three-day paid trial immediately after the interview. Marsh impressed his employers, and he was offered full-time employment as a trench shield builder.
Two weeks ago, he was promoted to the position of yards supervisor and now has his own company vehicle to drive.
Marsh said his father left the family when both he and his brother were very young, and they started mixing with the wrong crowd.
"I was always getting into fights, and grew up thinking it's cool to bully and hit people," he said.
"I was only 12 when I assaulted a teacher, and I also assaulted a police officer when I was a bit older."
Marsh was introduced to drugs in his teenage years and turned to stealing and robbing to fund his addiction.
"Looking back, it's just stupidity. I should have lived a life to make Mum proud, instead I was making her ashamed," he said.
Trenchmate administrator Emma Muir said it was the first time the company had employed an ex-convict but it has worked out well.
"We were just looking for a hard worker, and we were open to giving someone a chance and if they could prove that they can do the job then it's a win-win," she said.
"Tom's really committed to what he's doing and we feel he's an asset to the company."
Marsh said he feels "awesome" at being able to now financially support his family.
He has remained drug-free since the day he made the promise to his mother, and said doing so had inspired his brother and partner to also give up drugs.
When asked what his biggest wish was, Marsh said: "I've always wanted to make Mum proud, and I just wish she could have been around to see me now."