Ministry of Justice figures show that under the three strikes sentencing system no-one has yet been sentenced for the third time, triggering the maximum sentence, with parole only in exceptional circumstances.
In sentencing since 2010, 4464 people have received a first warning from a court, and 41 of those are on their second and final warning. But no-one has yet been sentenced for the third time.
The Sentencing and Parole Reform Act came into force four years ago. It creates a three-stage scale of increasing consequences for repeat serious violent offenders.
When someone is convicted of their first offence under the law, it stays on their record forever.
If subsequently convicted of a second qualifying offence, they are given a final warning. If sentenced to imprisonment, they must serve the full term without possibility of parole. The first and final warnings remain on the offender's record.
Offenders convicted for a third time automatically receive the maximum sentence, with parole only in exceptional circumstances.
The three strikes law now applies to 40 serious violent offences with a maximum penalty of seven years imprisonment or more.
The qualifying offences include murder, attempted murder, manslaughter, wounding with intent to cause grievous bodily harm, sexual violation, abduction, kidnapping, and aggravated robbery.
Most New Zealand courts only deliver a handful of first warnings every year, but Auckland District Court consistently delivers more than any other - it has handed out 555 first warnings and six final warnings since the law was introduced.