In evidence, Aaron Duggan, a Tauranga detective at the time, said Martin seemed “unemotional — not at all upset” when she and her husband came into the police station there at about 10.30am on January 25.
Martin told Det Duggan her husband phoned her at about 5.30am that morning to say that police had come looking for her at their Welcome Bay home. She didn’t know what it was about but then heard on the news that someone had died in a house fire at Whatatutu. She deduced it must have been her father and that was why police were trying to find her.
Det Duggan said Martin had asked, “Is the house OK?”
She also had a condescending manner when her brother John was mentioned, the detective said. .
“She said she felt buggered and tired and wanted to go have a chat with her counsellor.” She declined an offer to speak with police victim support.
Cross-examined by counsel Rachael Adams, Det Duggan agreed there was no standard way that people responded to bad news — some showed obvious emotion and others were more stoic.
In other evidence, the jury heard how in 2019 an undercover cop known as "Millie" was tasked with befriending the Martins. The following year, "Millie" divulged a false personal predicament to Martin designed to elicit conversation about arson.
Martin shared with “Millie” that she knew how to start a delayed fire using a pot of oil. She even went so far as to demonstrate the method on a camping oven in the backyard.
She was helping "Millie" refine a plant to burn down her and her estranged husband's jointly owned Dunedin house for an insurance claim and in the hope of getting rid of a personal diary she'd accidentally left at the property and which her husband was using to blackmail her.
At one point "Millie" said she didn't care if her ex-husband was in the house when it went up in flames. Martin told "Millie" not to contemplate the idea as she wouldn't want to have a murder charge hanging over her.
Once police were aware of the method Martin suggested to start the fire, they tasked David Neale - a former ESR scientist, now chief scientific adviser to the London fire brigade - to oversee a series of experiments carried out by the New Zealand Fire Training Centre in Rotorua.
Mr Neale said the tests showed the origin of the fire could have been in a pot on the right rear element of Russell’s stove. Flames that developed could have been big enough to start a major blaze.
From his analysis of the scene, the fire started somewhere central in the house — possibly the kitchen — but he couldn’t pinpoint the exact origin.
It was impossible to say what might have been in the pot as, left to continuously burn, there was no remaining trace of the contents.
Another witness David Ramsay — an electrical engineer and forensic electrical fire investigator - had been tasked with examining the remnants of various electrical items recovered from the property. His tests showed the fire could only have originated on the right rear element of the stovetop oven.
He said three porcelain oven control switches on the lefthand side of the stovetop oven were still intact. However, the four porcelain element controls on the right of the stove panel were completely burnt out. It showed that side of the stove had been subject to a much more intense heat than the lefthand side.
He pointed out other areas of damage to the stove top that supported his conclusion the right rear element had reached an extreme heat — consistent with a pot catching fire on it.
However, there was nothing left of the stove element controls to tell whether any of them were in the on or off position.
Milo Kral, a professor of mechanical engineering specialising in metallurgy at Canterbury University for the last 25 years, examined the stainless steel, copper-based pot the Crown alleged was used to start the fire. It had been found stuck hard to the right rear element of the stove that had toppled over in the fire.
Prof Kral said he had no knowledge of how the pot was allegedly implicated in the fire, only that it was “of interest”.
He analysed it against a similar pot and found that it had been damaged by extreme heat.
The copper base had almost melted or had melted. For that to have happened, it must have reached more than 1000 degrees Celsius.
He also examined the metal cover plate from the stove top control panel and found the righthand side of it had also been exposed to a heat much higher than the left-hand side — possibly hundreds of degrees hotter.
Evidence from more than 30 Crown witnesses is still to be heard in the trial that is expected to take up to five weeks.
Justice Helen Cull is presiding.
Read more:
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Accused’s husband: “She’s not someone who can live with the guilt of telling a lie”
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Cold case murder trial: Why John Allison believes his sister murdered their father
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