When Paul Russell Wilson is sentenced for his second murder, he could become the first person in New Zealand to be jailed until he dies.
Wilson, who changed his name to Paul Pounamu Tainui and was a groomsman at David Bain's wedding, pleaded guilty to raping Merivale woman Nicole Marie Tuxford, 27, on April 7. He had previously admitted her murder.
At the time of the killing, Wilson was on parole for the 1994 murder of his ex-girlfriend Kimberly Jean Schroder, 21, in Hokitika on the West Coast.
The Crown will seek life imprisonment without parole when he is sentenced on March 28. It has tried, and failed, to have such sentences imposed in the past.
Criminologist Professor Greg Newbold said Wilson would be a "prime candidate" to become New Zealand's first life-without-parole offender, but courts had in the past mis-applied the law.
According to the Sentencing Act 2002, the court "must" sentence offenders like Wilson to life without parole "unless the court is satisfied that, given the circumstances of the offence and the offender, it would be manifestly unjust to do so".
"In every single case so far, the courts have found life without parole to be manifestly unjust because they've changed the definition," Newbold said.
"What they've done is they've reversed the presumption so they are applying the third strike provision only in extreme circumstances, rather than avoiding it only in extreme circumstances."
Lawyer and former Act MP David Garrett, who introduced the "three strikes" legislation while in Parliament, said there had been eight third-strike cases so far.
In all cases except one, courts "miraculously" decided it would be unfair to apply the legislation, Garrett said. The exception was a case where a judge applied the full non-life sentence without parole.
"Aided by the Court of Appeal, judges have been deliberately mis-interpreting the clear intent of Parliament when the law was passed," he said.
"That clear intent was that, except in very rare cases, at stage three the person would serve the maximum sentence without parole."
Under three strikes law, Wilson could get life without parole even on his second strike, but "he can also get life without parole regardless of his strike history". Garrett said most lawyers were unaware it was an option regardless.
In a separate section of the Sentencing Act, if a court finds "no minimum term of imprisonment would be sufficient" to hold an offender accountable; denounce their conduct; deter them and others from committing similar crimes; or protect the community, a judge can order no parole.
"That's a long bit of legalese that says the sentence may be life without parole," Garrett said.
In August 2016, the Crown lost an appeal to sentence two convicted murderers who had already received a warning under the three-strike law to life sentences without parole.
Justin Vance Turner and Shane Pierre Harrison would have become New Zealand's first prisoners to be sentenced to life without parole for their separate murder convictions, after each already had a "first strike" offence.
Before the Crown's appeal, Turner was sentenced to serve at least 15 years of a life jail term before being considered for parole, and Harrison had to serve at least 13.
Turner had pleaded guilty to the murder of Maqbool Hussain in Balmoral, Auckland, in March 2014. He punched Hussain and described stomping on his head until it was bouncing off the pavement.
His first strike warning had been for wounding a woman in 2011, causing her traumatic brain injuries. He was out of jail from that sentence for about two months before murdering Hussain.
Harrison was found guilty of murder after a younger fellow Mongrel Mob Rogue shot Alonsio Matalasi, 25, in Petone in August 2013.
His first strike warning had been for indecently assaulting a female police officer by pinching her bottom and brushing his hand across her thigh and groin.
As a teenager he was convicted of manslaughter, but that was long before the three strikes legislation took effect.
In 2013, double child killer Jeremy McLaughlin escaped being sentenced to life in prison without parole. The Crown wanted him to be given the record sentence, but the High Court instead imposed a 23-year non-parole term.
Justice Graham Panckhurst said at the time McLaughlin was "on the brink" of becoming the first murderer in New Zealand to be jailed for the rest of his natural life.
McLaughlin was found guilty at trial of strangling schoolgirl Jade Bayliss, 13, stealing items from her family's Barrington St, Christchurch, home and torching it in November 2011.
In June, Justice Minister Andrew Little was forced to backtrack on a proposed repeal of the three strikes law. NZ First indicated it would not support it.