A law change allowing offenders to be kept behind bars after finishing their sentences came too late to save Blessie Gotingco.
Name suppression lifted yesterday for 28-year-old Tony Douglas Robertson who raped and murdered Mrs Gotingco in May 2014, only six months after being released on strict conditions after serving his full sentence for molesting and abducting a five-year-old girl.
Corrections Minister Sam Lotu-Iiga said the Government had since passed a public protection orders (PPO) law allowing "people like Robertson" to be detained in prison after their sentence ends if they pose a serious risk of reoffending.
"Sadly that was passed last December after this sad tragedy," he said.
There's no way of knowing if Robertson would have reached the threshold for a PPO as the law hasn't yet been tested, Corrections' northern region commissioner Jeanette Burns said.
At the time of Robertson's release, imposing strict conditions including GPS monitoring was all that could be done.
Mrs Gotingco's family are unhappy with Robertson's monitoring, but a Corrections review found staff went above and beyond in managing him.
"Sadly however, no amount of supervision, rehabilitation or tracking will deter an offender who is determined to commit a crime no matter the consequences," Ms Burns said.
She says it's the first time an offender being monitored by GPS has committed such a "heinous crime" in New Zealand.
Justice Minister Amy Adams said the situation showed there was no silver bullet that could prevent further reoffending.
"It highlights that while it's [GPS monitoring] a tool, it isn't the magic solution that some put it up to be."
She'll be asking questions about whether there are lessons to be learned from this case.