The Youth Court has been given new sentencing options for serious young offenders under legislation passed by Parliament today.
Social Development Minister Paula Bennett said the youth justice system worked for 95 percent of offenders -- but it wasn't working for the five percent at the hard end of criminal offending.
"That's about 900 to 1000 young people who are on a fast track to prison," she said.
"We are demanding real accountability from serious young offenders, and we are also offering them practical help to change their behaviour."
Under the law changes, the Youth Court's jurisdiction has been extended to cover the most serious 12-year-old and 13-year-old offenders and it has a wider range of sentencing options.
They include much longer supervision orders and enforced participation in rehabilitation, education and drug and alcohol programmes.
The parents of young offenders can be ordered to attend parenting programmes, so can the young offenders themselves if they have children.
Ms Bennett said it was essential to work much longer with serious young offenders, who were often the product of their environment.
"This is going to make a significant difference to young people's lives, those who have quite frankly been left on the scrapheap of despair that leads to adult jail. We won't give up on them."
Labour MP Jacinda Ardern said the bill was a blunt instrument for a much deeper problem that went back decades.
"If you put those 1000 young people in a room you would see the same characteristics in all of them -- disengagement with education and employment, subject to violence in the home, subject to drug and alcohol abuse and social deprivation," she said.
"We know what the causes and the catalysts are, it's up to us to intervene at the right point."
Ms Ardern said it was known that 80 percent of young offenders were under the influence of drugs or alcohol when they committed crimes.
"What are we doing to intervene before criminal offending occurs? I've seen no deep financial investment in that area."
Maori Party co-leader Pita Sharples had reservations about the bill and said the real issue was the need for adults to show leadership and support young people who were running into trouble.
"They have to know that we care about them...we have to make sure that they can have hope for their futures," he said.
Dr Sharples said unemployment was an important factor in the hopelessness felt by many young people, and Young Maori were the most severely affected.
The bill passed its third reading on a vote of 64 to 58. It was supported by National, ACT and United Future and opposed by Labour, the Greens, Progressives and Maori Party.