The number of second-strike offenders is rising, raising the question of whether the three-strikes law is much of a deterrent, a legal expert says.
The three-strikes law means offenders automatically receive the maximum sentence for a third serious violent or sexual offence, usually with no chance of parole.
Ben Bosch Herkt yesterday avoided being jailed for life without parole but was sentenced to life in prison with a minimum non-parole period of 12 years, for the murder of Matthew Greenslade in Papakura in 2014.
Justice Moore ruled that it would have been manifestly unjust for Herkt to not be eligible for parole.
Auckland University Law Professor Warren Brookbanks said special rules applied to murder, which were very severe.
"And it means in any case, if a person's committed a second strike on a charge of murder, the legislation says they must be imprisoned for life and that sentence has to be served without parole, unless the court is satisfied it would be manifestly unjust to do so, considering the circumstances of the offence and the offender.
Those type of cases were coming through the courts on a regular basis, Mr Brookbanks said.
"What's interesting about these cases that are coming through is that they tend to be repeating the demographic profile of the people of who are in our jails.
They were predominantly younger offenders, with a Maori or Pacific background, he said.
"The three offences which are being committed, and for which people are getting strikes, are typically robbery, sexual assault and violent assault.
"And in fact there are very few people who are receiving second strikes for crimes like murder. It's not a large number at all."
There had been well over 5000 first strike offenders since the legislation was introduced five years ago.
"Because those people have been in the system, they haven't been at liberty to commit a second strike. But now some of them have served their sentences and are in the community, so I think we're seeing more second strikes coming through."
It appeared judges were wary to impose such a harsh sentence on anyone, given no New Zealand judge had yet done it, he said.
"The prospect of locking somebody, who is 19 or 20, away for life without parole was a deeply disturbing prospect.
"And I think judges will work very hard in individual cases to find reasons to establish the presence of manifest injustice."
But at some point, he said there would be a case where the courts would have no alternative.
There were less than 100 second strike offenders at present, but that didn't mean the three strikes law was working, Mr Brookbanks said.