A man has been found guilty of murder over the shooting death of his 81-year-old mother, one hour after he killed his brother.
Paul Cohrs shot dead his brother in NSW and then his mother in Victoria, in October 2018, following a years-long family dispute.
He faced a 10-day trial in Victoria's Supreme Court over his mother Bette Schulz Cohrs' death, denying he had murdered her and arguing he was mentally impaired.
The relationship between Cohrs and his brother Raymond became strained in 2012 as they had conflicting ideas over the family business, the jury was told.
Raymond, who had the support of his mother, decided to get appraisals on properties connected to the family business, including a NSW border property that Cohrs and his wife were living in.
On October 30, 2018, Raymond and a real estate agent went to the property for the evaluation and were met at the gate by Cohrs.
The men drove to the shearing shed and Cohrs grabbed his shotgun and fired two rounds into his brother.
He then drove 120km to his mother's home, at Red Cliffs in Victoria's northwest, and shot her in the chest one hour later.
Cohrs' barrister claimed he had delusional disorder, urging the jury to find him not guilty on the basis of mental impairment as he could not have understood his actions were wrong.
But prosecutors said another psychiatrist had found Cohrs had the mental capacity to comprehend what he had done.
Jurors retired to deliberate on Monday morning, and returned within three hours with a guilty verdict for the murder charge.
Cohrs will face a pre-sentence hearing on September 10.
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