Matthew Fisher-Turner, then 24, died on October 1, 2016 after being stabbed repeatedly at the family’s Parmelia home.
His body was then buried in the back garden by his brother Joshua, then 26, and his sister Hannah, then 19 – which was not discovered for several weeks.
Fisher was jailed for life on Thursday with Justice Stephen Hall saying his actions were motivated by “hatred” and not self defence as he had claimed at trial.
Joshua was jailed for four years, and Hannah three years and eight months for being accessories – with Justice Hall saying they had been placed by their father in the position of having to make an “appalling” choice between helping their father or ruining the family.
But Justice Hall said, out of misguided loyalty, they both made they wrong one.
With parole eligibility, Hannah is eligible for release on August 28, while Joshua could be out of prison in October.
The trial earlier this year heard the murder occurred on the day the Western Bulldogs beat the Sydney Swans in the AFL season finale – and it was that match Fisher watched, less than two hours after he had repeatedly stabbed his son in the chest, killing him almost instantly.
Prosecutors argued – which was accepted by Justice Hall - that the killing was a pre-planned murder, with two sharp knives secreted in the shed of the house by Mr Fisher beforehand.
Fisher’s defence team had said there was no argument it was he who did the killing, but it was not murder because it was an act done in self-defence to protect himself and his other children.
That protection was needed, they said, because Matt was an angry, violent and abusive young man, using threats and force to “terrorise” the family for a year or longer.
Most of that violence was directed towards Mr Fisher, the court was told, but also impacted on his brother Joshua, and his sister Hannah.
It was those siblings who were instructed to bury the body in the back garden by Mr Fisher – and who were accused of being accessories to his murder.
The court was told the decline of the family had begun in March 2014 when Jill Fisher-Turner, the wife and mother who held the house together, died of cancer.
After her death, Fisher withdrew into himself, doing little inside or outside the house, and while the introverted Joshua and Hannah mostly studied and spent time by themselves, the outgoing Matthew partied with friends and girlfriends.
The “chalk and cheese” nature of the household caused increasing tensions – with Fisher’s lawyer Sam Vandongen describing the house as a “powderkeg”.
And the court heard evidence of Matthew’s increasing volatility, with 000 calls made by the family twice in 2015 about his threats.
A video shot on Matthew’s phone in the months before his death showed one such argument, with him taunting his brother, and Joshua shouting back.
In the background, Fisher could be heard saying to Matthew that he was “tearing this family apart”.
Prosecutor Laura Christian outlined how on the first Saturday in October 2016, another of those arguments – about who could use Ernie’s car that day – turned deadly.
When Matthew failed to turn up at his rigging job the following, Monday, questions began to be asked by friends, who were repeatedly told by Mr Fisher that his son had gone east with a “hot chick”.
But with Matthew’s car and phone still in Perth, those answers did not add up – and with a missing person’s report filed, police asked similar questions and got similar answers.
They did not accept them. And on further, official questioning in late October, Mr Fisher and his children all initially denied knowledge – before all capitulating.
“I couldn’t think of another solution ... I couldn’t come up with anything," Fisher eventually said.
“I knew I had to get the jump on him, he was powerful and agile - I think I’ve done the right thing, I really do, in a twisted way … he was an arsehole.”
In sentencing, Justice Hall said Fisher’s actions were “reprehensible” – with his exit soon after almost as bad.
“It is disturbing you thought killing your son was justified … you have shown no regret or remorse, and this callousness is confirmed by the treatment of Matthew’s body,” Judge Hall said.
And of Hannah and Josh, Judge Hall said they were presented with an “appalling dilemma that was not of your making.”
“You both made the wrong choice out of misguided loyalty to your father.
“The person who should have protected you … selfishly involved you in the offence.”
This article originally appeared on PerthNow.