A former wildlife carer unlawfully killed her non-verbal, frail mother by lacing her food with a drug known as "green dream", a NSW Supreme Court jury has found.
Barbara Eckersley, 69, was on Thursday found not guilty of murder but guilty of Mary White's manslaughter at an aged-care centre in August 2018.
Ms White, 92, a renowned environmental scientist, had severe dementia and other health conditions, having suffered a stroke in 2016.
She died two days before she was due to move out of the nursing home in Bundanoon in the NSW Southern Highlands to another facility in Coffs Harbour, closer to family.
Eckersley and her husband Richard visited on August 5 with the offender placing a small amount of a drug in Ms White's food.
The drug - known as "green dream" - was left over from Eckersley's working as a wildlife carer in Canberra about two decades earlier, the court was told.
It was used to euthanise native animals.
She added a small amount to her mother's food thinking Ms White would go to sleep, not that it would kill her, Eckersley's lawyer Kieran Ginges told the jury.
After telling detectives she had put drugs in her mother's meal, Eckersley was charged with murder.
At trial, Mr Ginges contended the drugs were not a significant cause of death, pointing to Ms White's heart condition, thrombosis and other health issues.
The former scientist was paralysed on the right side of her body and at the time of her death was incontinent, non-verbal and needed full-time care.
Crown prosecutor Paul Kerr had told the jury murder was usually associated with violence, mayhem, anger, revenge and jealousy.
He said that did not describe Eckersley - calling her a loving, caring and compassionate daughter.
But Mr Kerr said taking another life constitutes murder.
The jury, sitting in Goulburn, took a little more than a day to return its verdict.
Eckersley will be sentenced at a later date.
Australian Associated Press
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