A killer who hatched a "carefully planned murder" and viciously stabbed his ex-partner to death while she slept has lost a bid to take the case to the Supreme Court.
Ernest Smith was sentenced in 2013 to life imprisonment, with no chance of release for 17 years, for killing Amanda Taufale in her Tawa home in 2012.
At Smith's sentencing, Justice Ronald Young said it was a "carefully planned murder" by Smith, who waited for hours in Taufale's roof space and attacked her while she was asleep in her bed.
During a violent struggle, Smith stabbed and slashed the woman, who was mother to his 9-month-old baby, and left her to bleed to death.
He then tried to make it appear that an intruder had jimmied open a spare room to commit the crime.
Taufale's teenage son woke to find his mother's body the next morning.
More than half a decade after he was jailed, Smith made a bid to appeal to the Supreme Court.
In a decision released on Wednesday, the country's highest court said it wouldn't consider his case.
The court noted Smith's offending involved "the calculated planning, the fact that the offending had involved unlawful entry into the deceased's dwelling, the high degree of brutality, cruelty and callousness involved in the murder and the vulnerability of the deceased".
Smith's plan unravelled when he realised he had lost his car keys and stole Taufale's car to drive back to Karori, where he lived.
He also left behind a hood he wore during the attack, Justice Young said in 2013.
Taufale's uncle Ralph Jorgensen read a statement on behalf of the family when Smith was jailed.
"What happened to Mandy was absolutely shocking for the family and something none of us ever expected to happen.
"In regard to Ernest Smith the family is relieved that he finally entered a plea of guilty, and although the family cannot forget what happened, today's sentencing means they can now put this very dark period behind them and get their lives back together again."
The ordeal had been "harrowing", he said.
The two boys were being supported by the family. "The family is hugely supportive of the children and always will be."
Taufale's family thought the length of the sentence was appropriate, Jorgensen said.
Justice Young said the attack was planned to coincide with Taufale's vulnerability as she slept.
"This was a killing without mercy."
Crown prosecutor Grant Burston said it was a "particularly brutal and callous murder".
Taufale had a bachelor of applied science in psychology, and had worked with disabled men and women, disadvantaged youths and victims of domestic violence.
She had volunteered at Women's Refuge, and in the two years before her death had taken up a job at Industrial Research where she worked as a science support co-ordinator.