The officer in charge of a case where an elderly Wellington woman was violently killed in her home has explained why a mysterious, late-night doorknock at a different house on the street was discounted by investigators.

Julia DeLuney, 53, is on trial in the Wellington High Court for the murder of her 79-year-old mother, Helen Gregory.

The Crown case is that DeLuney killed Gregory at her Baroda St, Khandallah home on January 24 last year, then staged the scene to look like Gregory died after an accidental fall.

She claims she drove from the Khandallah property back to the Kāpiti Coast to get help after her mother fell from the attic, and that her mother was murdered in the 90 minutes that she was gone.

Her lawyer, Quentin Duff, has accused police of having “tunnel vision” when focusing on DeLuney as the suspect, instead of properly considering that someone else was responsible.

Julia DeLuney (left) is accused of killing her mother, Helen Gregory in an attack in Khandallah, Wellington.

He is questioning officer in charge Detective Senior Sergeant Tim Leitch today, and has asked why police did not place more weight on information about someone knocking on a door further down the street around the time of Gregory’s death.

The information came to police attention when the residents of the home approached a police officer on scene guard and explained somebody had knocked on their door late that night. The residents did not see anybody.

Leitch explained he tasked another detective with visiting the residents and taking a statement from them.

Duff suggested that Leitch referring to the information as “probably not relevant” in communications would influence other officers in how they handled it.

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Leitch said the detective who spoke to the residents was a “particularly thorough” person. He set the information aside for multiple reasons, including that the house was some distance away from Gregory’s, there were no other reports of doorknocks in the area or sightings of suspicious activity, and by that point in the investigation they already had strong information pointing towards DeLuney.

Duff has also accused Leitch of being the “genesis” of what he called the “attic myth”, saying Leitch wrongly believed DeLuney had claimed Gregory’s fatal injuries were sustained in the attic fall.

He argued DeLuney had said her mother suffered a fall but hadn’t noticed much blood or injury, then later returned to a “warzone” with blood spread through the house.

“She has never, ever said that what she saw was because of the fall from the attic,” he said.

Julia DeLuney, 53, is on trial in the Wellington High Court. Photo / Mark Mitchell

“She’s never once said or tried to say it was because she fell from the attic, has she?”

Leitch said DeLuney had not said that “in those words”.

Duff pointed to Leitch’s notebook entries the morning after the death, where he noted after a phone call with another officer “as a result of what he told me I understood the death to have likely been the result of a fall”.

But Duff said there was no evidence in any of the emails or statements Leitch had received that DeLuney had claimed the fall caused Gregory’s death.

“If that understanding is wrong, then the poison starts, doesn’t it? If that understanding is quite wrong, then we’ve got a problem don’t we?”

Leitch said he didn’t believe his understanding was wrong.

Duff pointed to the three scenarios that police considered: that the death was a result of a fall, that DeLuney had killed Gregory, or that a third person was responsible for the death.

Helen Gregory died in January last year after being attacked in her Khandallah home.

“There is a fourth scenario here,” Duff said. “There is an attic fall and somebody has turned up after Mrs DeLuney left.”

Leitch said he considered that as part of the third scenario.

“You never seriously, though, treated them like they could run together,” Duff said. “There is a fourth scenario that none of your writing suggests you ever grappled with, would you agree with that?”

Leitch did not agree, saying there were indications that a fall had occurred, and that something else had happened later.

“When you arrested Mrs DeLuney, you didn’t believe there had been a fall,” Duff said.

“By the time we arrested Mrs DeLuney I’m not sure whether that’s true or not, but I was sure she’d killed her mother,” Leitch replied. “The whole fall thing, there were a lot of indications that hadn’t happened . . . So yeah, I don’t believe there was a fall.”

Earlier this week the court heard detailed analysis of DeLuney’s bank transactions, showing in the year leading up to the death she spent more than $150,000 on cryptocurrency.

The court previously heard Gregory confided in friends in the months before her death that two large sums of money had gone missing from her house, including up to $85,000 her daughter later admitted to investing in crypto.

The trial continues.

Melissa Nightingale is a Wellington-based reporter who covers crime, justice and news in the capital. She joined the Herald in 2016 and has worked as a journalist for 10 years.