A Perth man who admitted being obsessed with serial killers and wrote about embracing his "darkness" before he murdered his three children, wife and mother-in-law is appealing his sentence of life without parole.
Anthony Robert Harvey, 25, pleaded guilty to murdering his family and became the first person in Western Australia ordered by a judge never to be eligible for parole.
But he is now fighting that decision by taking his case to the WA Court of Appeal.
Harvey killed two-year-old twins Alice and Beatrix, three-year-old Charlotte and their mother Mara Lee Harvey, 41, at their Bedford home on September 3, 2018.
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He killed grandmother Beverley Ann Quinn, 73, when she visited the next morning.
In his sentencing, Justice Stephen Hall said there was no case that was truly comparable to Harvey's crimes.
"Your actions were so far beyond the bounds of acceptable human conduct that they would instil horror and revulsion into even the most hardened of people," he said.
Justice Hall said Harvey failed in his duty as a parent "in the most extreme way imaginable".
In Harvey's journal he wrote about embracing his "darkness and animal instincts" and "doing the unthinkable to unshackle" himself from his family.
Ms Quinn and Ms Harvey were struck on the head with a 1.2 metre pipe and repeatedly stabbed with a newly purchased knife almost the size of a machete, while the children were murdered with a smaller knife.
Harvey remained at the house for days then gathered cash and travelled about 1500km north to Pannawonica where he turned himself in to police on September 9 with the help of his father.
