A Sydney grandfather who fatally stabbed his wife in a frenzied and sudden attack after suffering months of insomnia has been jailed for at least two years and six months.
Mu Rong Hong, 64, pleaded guilty to the manslaughter of his wife of 30 years, Mu Xia Hong, 57, at a relative's house at Berala on November 11, 2019.
He was originally charged with murder, but his plea was accepted on the basis of substantial impairment due to mental illness.
In the NSW Supreme Court on Thursday, Justice Peter Hamill jailed him for six years with a non-parole period of two years and six months.
"It is self-evident that this is a tragic case," he said.
The Hongs, who had two adult children, were said to have had a happy and normal marriage with no reports of any violence between them.
For 15 years, Hong ran a small convenience store in Westmead which he closed in April 2019 and stopped working.
He reported difficulty sleeping, was anxious and "appeared to descend into a severe melancholic depression".
His family assisted him in obtaining psychiatric help and he was assessed, diagnosed and treated at the Cumberland Hospital on November 4.
A week later he stabbed his wife more than 40 times with a kitchen knife.
He told police he killed her due to his "chaotic mind" and inability to sleep.
He "heard voices in his head" and "felt like he lost control of his body".
He said he had no disagreements with his wife and that they had lived together for a few decades, but he was "mentally nervous, I did something wrong, I regret".
"The offence was objectively very serious," the judge said.
"It involved the offender forming an intention to kill, and the infliction of more than 40 wounds to an innocent victim who was caring for him.
"The offence involved the use of a weapon and was committed in the proximity of young children.
"The injuries bespeak a savage and ferocious assault."
His moral culpability was diminished by his severe mental illness, although this was the reason his charge was reduced from murder to manslaughter.
Hong, who came to Australia from China in 1988, had no criminal history.
"I am satisfied that if he is treated properly for his psychiatric illness, and complies with his doctors' advice, his prospects of rehabilitation are good and that he is unlikely to offend again," Justice Hamill said.