16 Feb 2021

Perth man found not guilty of murdering mother and siblings on grounds of insanity

11:35 am on 16 February 2021

A Perth man has been found not guilty by reason of unsoundness of mind of murdering his mother, sister and half-brother in their Ellenbrook home.

Teancum Vernon Petersen-Crofts was charged with the murders of his 48-year-old mother, her 15-year-old daughter and eight-year-old son in Perth.

Teancum Petersen-Crofts. Photo: Facebook/Teancum Vernon Petersen-Crofts

Teancum Petersen-Crofts, now 21, had pleaded not guilty to stabbing to death 48-year-old Michelle Petersen, 15-year-old Bella and eight-year-old Rua, in their Brixton Crescent home in the north-eastern suburb of Ellenbrook in the early hours of the morning on 15 July, 2018.

Delivering his judgement, Chief Justice Peter Quinlan said he was satisfied Petersen-Crofts killed all three of his family members and at the time he was not criminally responsible on account of unsoundness of mind.

"In particular I find you were suffering from schizophrenia," Justice Quinlan told the Supreme Court.

He said Petersen-Crofts suffered from the illness since he was 14 or 15 years old and was suffering from the symptoms at the time of the murders.

Petersen-Crofts sat in the dock with a support worker by his side, while members of his family sat at the back of the court.

His 48-year-old mother Michelle Peterson suffered 54 wounds, while his sister Bella and half-brother Rua were stabbed more than 40 times.

Peterson-Crofts had pleaded not guilty by reason of unsoundness of mind.

The trial only heard evidence about his mental state.

Petersen-Crofts 'receiving commands from different gods'

Petersen-Croft's family members cried and held each other as the verdict was delivered.

Justice Quinlan said hallucinations and delusions "compelled you to act in the way that you did".

He said the 21-year-old believed he was receiving commands from different gods, "voices telling you that you must kill your family to save yourself and the world".

Justice Quinlan said he was satisfied Petersen-Crofts could not control the voices and commands, and that they appeared real to him.

"You did not have the capacity to know what you were doing was wrong - you believed that your actions, as horrifying as they were, were the right thing to do," he said.

He said the young man was not criminally responsible for what he had done.

"We, the whole community, have failed you," Justice Quinlans said.

He said the community had also failed his mother and siblings and must do better to help people in the community in their position.

Outside the court Michelle Petersen's mother and Petersen-Crofts's grandmother Anna Mclean said the day had been exhausting.

"I feel so overwhelmed - you don't know how I feel," she said.

"But today has been really exhausting.

"And the outcome has come. What more could we ask for?

"His mother, up there, was looking down."

Petersen-Crofts will be detained in a mental health hospital under the Mentally Impaired Accused Act.


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