Lee-Anne Cartier has rejected an offer from police, which would have seen her reimbursed for costs she incurred trying to expose her brother's killer.
In a statement this morning, Detective Inspector Tom Fitzgerald said Cartier had indicated she intended to pursue ''wider compensation''.
The announcement came as Helen Elizabeth Milner, 50, was sentenced to a minimum of 17 years behind bars for the murder of Philip James Nisbet.
Police have acknowledged that the case may never have made it to court had it not been for the sleuthing of Cartier and the keen eye of a coroner.
An internal report showed detectives made many basic errors during an initial investigation which concluded Nisbet, 47, had committed suicide at his Checketts Ave home in Halswell in May 2009.
After a coroner found no evidence that the truck driver intended to kill himself, police launched a murder investigation and Milner was arrested in October 2011.
The Crown said she probably mixed the drug Phenergan with her husband's dinner and then may have suffocated him once he was sedated. She then manipulated the scene and fabricated a suicide cellphone text and suicide notes to cover her tracks.
The jury also heard that Milner tried to kill him in a similar fashion about a month earlier, motivated by his $250,000 life insurance policy.
This morning, Fitzgerald said police had apologised to Cartier and acknowledged the short comings of the initial investigation.
''The issues in the first inquiry were not primarily about individual officers, but about the structures and processes that were in place at that time,'' he said.
Outside court, Cartier would not discuss her bid for compensation from police.
JUDGE TO MILNER: 'MOST PERNICIOUS OF CRIMES'
Justice David Gendall told Milner at her sentencing in the High Court at Christchurch: "Murder by poisoning has always been seen as amongst the most pernicious of crimes."
The Crown asked for a minimum 18-year non-parole term as part of Helen Elizabeth Milner's life prison term for murdering her husband.
Milner, 50, continues to deny her guilt in the death Philip James Nisbet, who the Crown alleges she poisoned with an anti-allergy medication and then probably smothered as he lay unconscious in bed.
She was found guilty of murder and attempted murder at a trial in the High Court in Christchurch in December. She was acquitted on one attempted murder charge.
Justice Gendall noted she had depression, anxiety, with occasional panic attacks, a propensity towards violence, relationship difficulties and "an unhelpful lifestyle".
He noted she had previous convictions for stealing from her employer about the time of the murder, and perverting the course of justice for getting her son arrested for a crime.
On the Crown theory of the case, she had talked herself into murdering her husband simply for financial gain or to end the relationship after the expiry of the suicide clause in her husband's life insurance policy.
She had carried out the murder and then staged the death as a suicide, which included writing several suicide notes.
She had obtained the drug involved, phenergan, with a series of purchases from pharmacies under false names.
Justice Gendall offered his sympathies to the families involved. The death had been a tragedy, he said.
He told Milner: "There can hardly be a clearer case of calculated pre-planning than the case before me."
Crown prosecutor Brent Stanaway said the evidence and verdicts showed that she had planned the poisoning and had then staged his death as a suicide.
Because the murder involved calculated or lengthy planning, it meant an 18-year sentence was appropriate.
"It is rare for a victim to tell so many people of a desire to kill her victim, as she did in this case," he said. P
oisoning had always been seen as a pernicious form of murder, involving planning, subterfuge, against an unsuspecting victim.
He said Phil Nisbet had loved Milner and had strived to please her. He said if her motive had not been financial it was simply to get rid of a man who was no longer wanted in her life.
Defence counsel Rupert Glover argued that the case did not warrant the high non-parole term.
He said there had been no lengthy planning or calculation by Milner, and there was evidence that she had not been aware that she was the sole beneficiary of his life insurance policy until two weeks after his death.
He submitted that Milner's comments about killing her husband - comments that earned her the Black Widow title among her work colleagues - were never meant to be taken seriously.
He referred to Milner's "immense error of judgment".
"But to suggest it was coldly premeditated is submitted as taking the matter too far."
Milner appeared in the dock flanked by women prison officers. When the registrar made the usual inquiry as to whether there was any reason she should not be sentenced by this court, she replied, "No, ma'am."
The court heard nine victim impact statements from family members.
Lee-Ann Cartier, of Australia's Sunshine Coast, said she had an amazing relationship with her big brother, Phil Nisbet before Milner came into their lives.
"Helen has taken away so many future memories we would have had."
She had also taken years off her elderly parents' lives, and taken away their father from Phil Nisbet's two sons.
"Rest in peace, Philip. You will always be my big brother."
She told Milner the sentencing would allow her to "evict you from my head space until you come up for parole".
Cartier's twin daughters' statement about the loss of their Uncle Phil was read to the court.James Nisbet,
Phil Nisbet's 81-year-old father, who lives in Australia said his son's untimely death had seen his own health and memory rapidly decline.
He said she carried out the crime to start a new life with a new man and the health insurance money.
Phil Nisbet's mother, Yvonne Nisbet, said the trial had been "horrible".
It had been heart-wrenching to her all the lies and deceit.
She recalled Helen comforting her after her son's death, knowing that she was the one who had killed him.
Andrew Nisbet said Milner had "robbed me of a future with my little brother".
Adam Kearns, 23, the stepson of Phil Nisbet, said he had realised that his mother had killed his stepfather.
Kearns said he had spent 16 days in jail after Milner had got him wrongly accused and arrested for a crime.
The trial had been stressful and overwhelming. He had just started counselling, and was looking forward to moving on with his life and putting everything behind him.
Milner stood with head bowed in the dock as the sentence was imposed.
Outside court, Glover said he had spoken to Milner after sentencing.
''She's just taking stock of her situation. It's a difficult thing to face - a life sentence with a long minimum period of imprisonment.''
Milner maintained her innocence and Glover said he was waiting to hear whether she wanted to appeal the sentence and murder conviction.
Clutching her brother's ashes on the court's steps, Lee-Anne Cartier thanked everyone for their support and police for their hard work in bringing her brother's killer to justice.
''We're happy with the sentence,'' she said.
''He [Philip Nisbet] can finally now rest in peace because it's over. He's got closure, we've got closure.''
Cartier said she would attend every parole hearing to make sure Milner ''never walks the streets of New Zealand again''.
She would not discuss her bid for compensation from police.
Andrew Nisbet said: ''We're just finally pleased to have justice for our brother. It's great for mum and dad to now have closure.''
Milner was given a first strike warning under the regime that imposes additional penalties on repeat violent offenders.
- The Press
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