A Supreme Court judge has ruled that a Perth man who bludgeoned his parents to death should not be held criminally responsible for his actions because he was suffering a mental impairment at the time.
On April 26 last year, Myles Taylor used a geologist's geo pick hammer to attack his 65-year-old father Michael and 64-year-old mother Lesley in the lounge room of their Hocking home.
The 36-year-old then called triple zero and told the operator: "Better send a police car around".
When asked why, he said "I just killed my parents", and when asked what happened, he replied "I think everyone knows..."
Lesley Taylor died at the scene, while her husband was rushed to hospital but died from his injuries two days later.
Myles Taylor was charged with two counts of murder and faced a judge-alone trial before Justice Anthony Derrick earlier this month.
He admitted responsibility for their deaths but maintains he was suffering a mental illness, which meant he could not control his actions.
The hearing was told in the days before the killings the 36-year-old had called police because he wanted help with birds he was seeing on the walls and the faces, on his bed sheets.
When police did a welfare check, Mr and Mrs Taylor expressed concerns about their son's unpredictable behaviour and revealed they had been locking their bedroom door at night.
While police felt they could not detain Myles under the Mental Health Act, they did give his parents advice about applying for a family violence restraining order.
The fatal attacks happened 13 days later.
In an interview with police, Mr Taylor revealed he had been hearing voices since he was 17 and it had become worse in the 10 months before the killings.
Psychiatrists testified at the trial that in their opinion Myles was suffering from a form of schizophrenia at the time of the killings.
They said this deprived him of the capacity to control his actions and to know, that he ought not do what he did.
In the Supreme Court today Justice Derrick imposed a custody order on Mr Taylor.