A mentally ill man who was infatuated with a woman used her electric guitar to kill her partner as the couple slept in their bed, a judge has found.
Michele Noel Risi said he had wanted to protect her from what he believed to be domestic violence by her partner.
Risi, then 35, was charged with murdering Shannon Weller, 36, and assault occasioning actual bodily harm to Allyson Thornton, 31, on March 23, 2020 at their Gladesville unit.
After a special hearing in the NSW Supreme Court, Justice Robert Allan Hulme on Friday found the offences proven but Risi not criminally responsible for them.
"I am satisfied that Mr Risi did not know that his acts were wrong because of a mental health impairment which led to his delusional view that Ms Thornton was in danger and needed his help," he said.
While Risi did not concede he caused the fatal injuries and assaulted Ms Thornton, the judge accepted the Crown had proved its case.
He used a ladder to get into the unit before striking Mr Weller in the head with Ms Thornton's white electric guitar which had been resting against a wall.
The judge said there was no dispute that Risi developed an infatuation with Ms Thornton whom he first met on March 3.
On March 11 he tried to break into a unit he mistakenly thought was hers, saying he wanted to protect her from her partner.
Ms Thornton testified she had been with Mr Shannon for six years and while they had verbal fights, they were never physical.
She had seen Risi around the complex, spoken to him a number of times and had picked up his interest in her.
"However, she never said anything to indicate that she had any such interest in him," the judge said.
Risi sent texts, from a phone of a mutual acquaintance, referring to her as "babe", and saying "I love you".
But Ms Thornton testified she took a blase approach to her phone and skimmed these messages thinking they were from the acquaintance.
On March 23, he sent messages asking Ms Thornton to marry him expressing that he wanted to "make love" to her and spend the rest of his life with her.
She didn't receive them because her phone was switched off.
She testified to being woken unexpectedly to see Risi standing to the side of the bed holding her guitar before he struck Mr Weller with full force.
While she only saw one strike, she concluded her partner had been hit multiple times as he was injured and had blood on him.
"She threw herself on top of Mr Weller in order to protect him, and her leg was hit by the guitar being swung by Mr Risi," the judge said.
He yelled "he'll never hit you again" and later tried to encourage her to leave with him.
The judge said Risi's cognitive and mental health complications appeared to date back to his youth when he was struck over the head with a beer bottle causing internal bleeding on his brain.
His behaviour changed after having a metal plate inserted, suffering from depression and post traumatic stress disorder.
He had a long history of seeing professionals and attending hospital emergency departments for mental health related issues.
Two consultant forensic psychiatrists gave evidence opining that Risi had a mental health impairment involving PTSD and a psychotic illness, as well as a cognitive impairment.
His delusional beliefs continued and as recently as February he told a medical officer that he thought Ms Thornton "likes him and wants to be in a relationship".
Australian Associated Press
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