The killer of Angry Anderson's son could be released within four years after demonic beliefs and drug-induced psychosis led him to beat his best mate to death.
Mathew Flame, now 22, was suffering an acute psychotic episode when he beat and kicked Liam Anderson to death in a park on Sydney's northern beaches about sunrise on November 4, 2018.
Mr Anderson, 26, left a friend's nearby home in pursuit of his psychologically distressed best mate before he was set upon with fists, feet and possibly a rock found at the scene.
"(He) was completely innocent, his death was absolutely undeserved, and he had done nothing whatsoever to provoke it," NSW Supreme Court Justice Richard Button said on Wednesday.
"His final ordeal was extended, gruelling, terrifying and horrifically painful."
The psychotic episode had been sparked after Flame, who'd been partying all night with Mr Anderson and other friends, took a 10th MDMA capsule about 5am.
Unknown to the victim, who told another he would help his mate through the episode, Flame had become divorced from reality.
"Even accepting he could see with his eyes that the person whom he was harming had the appearance of his friend, I also accept that the offender believed that the recipient of his violence was demonic," Justice Button said.
"Although there was an intention to kill, as readily demonstrated by the brutality of the fatal acts themselves, there was never a real desire to bring the life of a human being to an end, let alone that of a close friend, as demonstrated by the reaction of the offender once he realised what he had done."
Justice Button, noting the case "cries out" for a special granting of a shorter non-parole period, jailed Flame for a minimum of five years and six months.
His full sentence of eight years will expire in November 2026.
Rose Tattoo frontman Gary "Angry" Anderson watched the sentence from a balcony in the courtroom, having told the court last week how his son's generosity and caring nature was met with fatal violence.
He also spoke of a spiral of love between parent, child and the children of that child - a structure that should be endless but is now broken, Justice Button said.
"No person with feelings can fail to be moved by those heartfelt statements of suffering," the judge said.
"And no sentence that I ... impose can relieve that pain."
Flame was still psychotic when confronted by police and frothed at the mouth while in custody.
But the realisation of the awfulness of his actions set in hours later and he'd been deeply remorseful ever since, the judge said.
During his trial this year, Flame pleaded not guilty to murder on the grounds of mental illness before a jury found him guilty of manslaughter.
While in custody, he developed the chronic and severe mental illness of schizophrenia, for which he now takes medication.
The trial heard how some months before taking his mate's life, he'd also mixed cannabis, alcohol and MDMA and - for a moment after arriving to work - believe his colleagues were demons.
Justice Button said it was easy to say with the benefit of hindsight that the episode should have led Flame to refrain from prohibited drugs or, at the very least, to stop mixing them.
But nevertheless, it had been a warning and increased Flame's moral culpability.
Outside court on Wednesday, the elder Mr Anderson reinforced to reporters how it had been two years since "our Liam" had his life taken.
"Two years ago, our family and those who love him started a lifetime sentence," he said.
Australian Associated Press
