Some of the bizarre details behind the 'Black Widow' murder case are now being revealed, including the son she framed and the unusual alias she used.
Helen Milner, 50, was today found guilty by a jury at the High Court in Christchurch of murdering her 47-year-old second husband.
The Crown proved that the woman known as the Black Widow had slipped the sedative Phenergan into Mr Nisbet's evening meal and, while he was heavily sedated, finished him off with a pillow.
Helen Milner bought drugs to murder her husband Phil Nisbet with under the alias of another would-be poisoner and is being sued by her son for $60,000 after she framed him for a crime he never committed.
Meanwhile, a senior police officer has acknowledged significant flaws in the way Mr Nisbet's death was first investigated.
An unlikely alias
Milner bought drugs to murder her husband with under the alias of another would-be poisoner.
Her murder trial heard that a woman calling herself Andrea Wilson used cash to buy a box of the sedative Phenergan at a Christchurch chemist on April 14, 2009 - the day before police say she first tried to kill Phil Nisbet.
In 2002, Wilson, who worked as a personal banker in Auckland, was convicted of trying to kill her partner by lacing his dinner with sleeping tablets. The tablets left a sour taste and Mr French left it unfinished.
Wilson later put lavender oil on his pillow to help him sleep then poured petrol through their North Shore home. The blaze caused extensive damage but nobody was hurt.
She was jailed for attempted murder, theft as a servant, forgery, and arson.
Detective Inspector Greg Murton, who led the homicide investigation into Mr Nisbet's death told the trial he thought it was critical to find out when and where the Phenergan was purchased, and by whom.
Pharmacists called as Crown witnesses said they trawled through their records to find that an Andrea Wilson bought a box of 25mg Phenergan at a pharmacy in South City mall under a fake address.
Milner's bank card had been used minutes earlier to make a $20 withdrawal at an ATM metres away, the jury heard.
In New Zealand, a name and address must be given when buying promethazine hydrochloride but no photo ID is required.
An angry son
Milner's son is now suing her for $60,000 after she framed him for a crime he never committed.
Adam Kearns, 18, spent 18 days in jail, set up by his mother who sent herself violent death threat texts and pretended they came from him.
Mr Kearns was arrested, denied bail, and spent 18 days in jail for a crime he didn't do.
Milner was jailed in August last year for two years and eight months for perverting the course of justice in framing her son.
Mr Kearns' lawyer Kerry Cook confirmed he is seeking $60,000 in damages from Milner.
Mr Cook said his client is suing over a "malicious prosecution ... that she knew to be false''.
"I've got instructions to file a claim against Milner for the time Adam wrongly spent in jail,'' Mr Cook said.
A letter of demand was served on Milner during her High Court murder trial, he said. Milner had yet to respond.
A botched investigation
The botched first police investigation into Mr Nisbet's death is a stark reminder for officers to keep an open mind in all inquiries, legal experts say.
"What's clearly happened here is that, too early on, police have made a decision on what they think the circumstances are and that's formed their theory of the scene. They've formed that in their minds too early,'' said Dr Chris Gallavin, dean of law at the University of Canterbury.
"For sudden deaths like this, even though it's probably very upsetting for the family, they ought to go in with quite a suspicious mind from day one and treat it like a crime scene right from the first moment. You don't want to have things blow up in their face like this.''
Police originally ruled the death as suicide and a homicide investigation was launched two years later only after a coroner raised doubts over the circumstances.
In the United States, a coroner carries out their own investigations into a murder or sudden death separately to police.
But in New Zealand, the coroner is reliant on information passed to them by police.
"So that really accentuates the embarrassment in this case - it's not like the coroner was looking at anything new,'' Dr Gallavin said.
Nigel Hampton QC, one of New Zealand's top defence lawyers, said the first 24-48 hours after a death are the "absolutely critical'' period in establishing what has happened.
The scene needs to be secured early to ensure nothing is contaminated and officers should seize "absolutely everything'' that may be relevant to an investigation.
"If it's a sudden death, or suspicious death, whatever, it's going to end up at a coroner's inquiry at the very least, therefore, forensic evidences should be collected from that point of view alone.''
While poisoning, as a form of murder, has "fallen out of fashion'' since its heyday in Victorian times, this case might act as a "bit of a wake up call'' for New Zealand Police, Mr Hampton said.
"It shows that poisoning is still a possibility in this day and age,'' he said.
"Police officers who are not trained in the practical sense of dealing with it should now be keeping it in the back of their mind when investigating sudden or suspicious deaths.''