Initially, Phillip Beale tried to say he was having a "mental breakdown" and couldn't remember the prolonged beating that killed his 84-year-old mother.

On Tuesday morning he told the High Court at Auckland, where he was on trial for murder, that he only remembered "hooking" his mother Joan Beale once, to the left side of her face.

But after a Crown lawyer took Beale through photos of blood spattered through the house he shared with his elderly mum, and her injuries, the 51-year-old stopped the seven-day trial and pleaded guilty.

Moments before, Crown prosecutor Chris Howard questioned Beale, asking if he was being "selective" in remembering only before and after the assault to try to "minimise" what he had done.

"Nah, I was in a mental breakdown, don't remember half the things," Beale replied.

When court opened in the morning, Beale said he was the youngest of five siblings, left school when he was 13 and was "illiterate".

When he left school, he did "nothing" and, because of those issues, lived off a sickness benefit and began smoking cannabis.

"I'd just go play video games and go down the road and hang out," he told the court.

He said he has lived with his mother all his life and started consuming methamphetamine when he was about 27.

His mother liked doing everything for him, he said, including his laundry.

In the days surrounding August 7, 2025, when Joan Beale died, Phillip Beale reported nothing unusual was going on at home.

His lawyer Kelly-Ann Stoikoff asked about what his neighbours had told the trial, that his behaviour was getting increasingly bizarre before his mother's death.

Beale replied he was having a "mental breakdown", of which he'd had a few and he would usually go to hospital, take medication and "come right".

He spoke about August 7, 2025, when he walked back and forth from their home in Papatoetoe, South Auckland, and the local shops.

He said he was trying to source methamphetamine that day, getting $600 from an ATM with his mother's card.

Borrowing $100 or $200 from his mum was normal and something he did every week, he said.

He wasn't able to get the drug that day, he said, and last smoked it a couple of days previously.

He said he remembered hitting his mother once that evening and her stumbling down and him "just freaking out".

He claimed he then doused himself in petrol and tried to set himself alight.

"'Cause I hurt my mum and I was feeling a bit ... I was surprised that I did it and was in shock."

He said he decided it was "too late now", left the house and jumped off a bridge.

Stoikoff asked Beale if after he first punched his mother, there was a moment where he thought, "oh, mum might die here".

Beale replied, "yes", after he hit her, because she was too old and it was not good. But he couldn't remember if he kept hitting her after that.

Howard then pointed out to Beale that the victim was 84, 1.58m tall and weighed about 48kg before she died.

The prosecutor asked where Beale remembered first hitting his mother.

Beale said he wasn't sure.

Howard then took Beale through photos of Joan Beale's injuries, which included bruising inside and outside her mouth, behind her ear, chest and legs.

There was also internal bleeding around her brain and multiple bruises to her legs, Howard said.

She also had "significant" wounding to her left hand and arm, which Howard said were consistent with her trying to defend herself.

The bruising to her lower legs, Howard suggested, was from Beale attacking his mother while she was lying "vulnerable and defenceless on the ground", which Beale denied.

The prosecutor suggested the only reason Beale would go so far and beat his mother so badly was because he intended to kill or injure her.

Beale disagreed, saying he loved his mother, didn't mean to kill her and didn't know what he was doing.

"I was paranoid I thought people were out to get me."

Blood, Luminol and a porcelain rabbit

Then Howard took Beale through photos of the blood spatter analysis and Luminol tests done at the scene.

This evidence, he said, showed Beale had hit his mother, dragged her to her bedroom and then kept assaulting her, which Beale either denied or claimed he couldn't remember doing.

Beale said he remembered afterwards getting a can of petrol from the garage to light himself on fire.

Howard suggested Beale was trying to light the house on fire and "incinerate" his mother's body, which Beale denied.

Howard also asked if Beale was being "selective" with the things he remembered.

"Nah, I was in a mental breakdown, don't remember half the things," Beale replied.

The prosecutor continued, asking Beale if he was only remembering the things that were less "nasty" about the assault.

Howard next turned to the subject of a porcelain rabbit doorstop, which he said was found at the scene covered in Joan Beale's blood.

Beale said as far as he could recall, he didn't use the doorstop to strike his mother.

Murderous intent

The court heard Beale reportedly told a police officer after the assault that he had beaten his mother "half to death".

Howard said that was a "bit of a step up" from a single punch and Beale must have known he was killing his mother.

"No, I don't know, by that stage I black out and don't remember," Beale replied.

Howard questioned why Beale could remember "all sorts", including first punching his mum and getting petrol and a lighter, but not the "gap" of the fatal assault.

"You must have continued knowing that you could kill her?"

"No, I didn't know that ... I didn't give it a thought," Beale answered.

Before the Crown and the defence were due to give their closing remarks, the court broke for 30 minutes.

When the jury returned, Beale pleaded guilty to his mother's murder.

He is due to be sentenced in November.

* This story originally appeared in the New Zealand Herald.