A woman who killed her husband gave "an Academy Award-winning performance" if a video she recorded was part of a plan to get away with murder, her barrister says.
Dale Vella, 54, shot her husband Mark Anthony Vella as he slept at their Murrumbateman home in the state's southern tablelands in August 2021.
"Yes, she took the life of her children's father. Was it murder? That's the decision you have to make," defence barrister Greg Hoare told the NSW Supreme Court jury on Thursday.
Her husband's friend told the trial Vella said: "I was going to shoot myself, but I shot him" as she asked him to call an ambulance.
Vella told the court she didn't know what happened in the time between just before she shot her husband in the eye and her arrest later that night.
She does not dispute doing it.
Her guilty plea to manslaughter was rejected by the Crown and she has pleaded not guilty to murder.
On the day she killed her husband, Vella recorded a video on her phone.
"I'm sorry guys, I just can't live like this anymore," Vella said.
"I've let him abuse you emotionally for years, and I've never protected you.
"I'm sorry I left everything in such a mess ... I've tried leaving, I've tried pushing him away. He doesn't care about anyone but himself."
Mr Hoare referred to the video as a suicide note.
"If that is a deception, that is an Academy Award-winning performance," he said.
Vella would have to prove it was more likely than not her capacity to understand, control or judge her actions were substantially affected by a mental health impairment when she shot her husband, or be found guilty of murder, Justice Helen Wilson instructed the jury on Thursday.
Crown prosecutor Kate Ratcliffe earlier said Vella was not impaired to the point it warranted reduction to manslaughter, inviting the jury to find her guilty of murder.
She quoted what Vella said after the shooting.
"'He can't hurt us anymore,' that's what (she) told her daughter," Ms Ratcliffe said, describing it as a "deliberate shooting".
"She shot him at that moment because she wanted to kill him."
Mr Hoare submitted Vella was not attempting to escape responsibility, telling the jury to find her guilty of manslaughter instead.
"Before this trial even started, she accepts she killed her husband, she accepts it was legally wrong and that, to put it bluntly, she needs to pay the price," he said.
He told the jury to examine what Vella told her daughter after the shooting closely.
"Did she really understand what she'd done or was this just a statement of the bleeding obvious from a woman deeply, deeply depressed?"
Attempts to prove Vella decided, "in the clear, cold light of day", to murder her legally-blind husband because she'd had enough of caring for him after 23 years might show the jury the opposite, Mr Hoare said.
"She continued for years to look after this man ... to care for him despite his ongoing abuse of her," Mr Hoare said.
Ms Ratcliffe reminded the jury Vella's deceased husband is not the one on trial.
She suggested her evidence about their relationship was "an exaggerated and untrue account about her husband's conduct towards her".
"This wasn't a mistake, it wasn't a suicide gone horribly wrong," Ms Ratcliffe said.
The jury will retire to consider a verdict on Friday following final instructions from Justice Wilson.
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