Supplied (GWN7)
)A WA man who claimed he was "cursed" and driven by "the devil" when he fatally attacked a lifelong friend with a machete has been sentenced to life in jail with an 18-year minimum.
WARNING: This story contains graphic content that some readers may find upsetting.
Gregory John William Quartermaine, 42, was found guilty of murdering 60-year-old Wilfred Williams at a house in the Great Southern town of Tambellup, where a number of children were present, in August 2019.
Quartermaine was under the influence of methylamphetamine and turned up at the house, where his mother lived, around midnight, stating his intention to kill Mr Williams.
He then attacked him over about half an hour with a machete and other sharp weapons, in what Supreme Court Justice Stephen Hall today called an "extraordinarily brutal explosion of violence".
Attack left 'most horrific scene'
At the start of the attack, Mr Williams was heard pleading for his life, as the other adults and the children in the house fled the scene.
Mr Williams suffered terrible injuries, including being decapitated and disfigured, before police and paramedics arrived to find what Justice Hall described as a "most horrific scene".
Justice Hall paid tribute to them, saying what they found must have left an indelible mark on them, and their service to the community was deserving of recognition.
He also noted the effect the attack had on the children who were at the house, saying their safety was at risk and they had been left traumatised.
Quartermaine pleaded not guilty to the murder charge and at his trial argued he was not able to control his actions because of the drugs he had taken, which made him delusional.
He initially denied any recollection of what he had done, but later told police the devil made him attack Mr Williams.
'Your choice' to use drugs: judge
The court heard Quartermaine first started using methylamphetamine in his 20s and had previously experienced adverse affects from taking the drugs, including psychosis.
But he continued using drugs and made no effort to stop.
Today, Justice Hall told Quartermaine he must "bear full responsibility for his terrible offence".
"You cannot avoid the fact it was your choice to use these dangerous drugs," he said.
Justice Hall accepted that the murder was not planned or driven by animosity, but he said it was aggravated by a number of factors, including its brutal and sustained nature.
Quartermaine, who sat with his head in hands throughout most of today's proceedings, will first be eligible for release on parole in 2037.
