ONLY one man will ever truly know what happened to murdered Byron businessman Jack Garda in the moments leading up to his death and he will have at least the next 21 years behind bars to think about it.
Kevin Malcolm Purtill was sentenced on Friday for the "unexpected and particularly violent death" of Mr Garda, 60, at a Lennox Head unit in February, 2010.
Justice Ian Harrison found that while Purtill's "continued silence means what actually happened may never be known", he was satisfied he had cut Mr Garda's throat with a large knife over drugs - most likely cocaine.
He said the reason for Purtill's attack remained unexplained and was, "except in the most general and speculative way, inexplicable".
Suspicion had been raised about Purtill's involvement in Mr Garda's February 8 disappearance, when his brother Warren was arrested and charged for making a series of purchases with the deceased's credit cards.
Soon after, Purtill attended the Lismore Police Station and handed investigators a map revealing where Mr Garda had been buried.
The court heard Purtill and his brother had placed Mr Garda's body in a canvas swag, loaded it onto the rear of Warren's ute and driven it south to Broadwater where they dug a shallow grave.
When Mr Garda's body was found, he was dressed in his underpants, shorts and socks and a surgical glove was on his right hand.
Purtill had claimed it was his brother who killed Mr Garda but that was rejected by a jury.
His brother, who pleaded guilty to accessory after the fact in February last year, said on the day Mr Garda was killed he had heard someone screaming from upstairs "I'll kill you, you f****** c***".
He said when he walked into the kitchen he saw "blood everywhere" and Mr Garda lying dead on the floor.
He also said Purtill had told him Mr Garda had tried to kill him and that they couldn't call the police because "this guy hangs around with heavy hitters".
During the trial Purtill's lawyer described how his childhood had been marred by domestic violence, dyslexia - he read his first books in jail - attention deficit disorder and marijuana abuse.
His troubles continued when he left school, experimented with his sexuality and moved in with a gay bouncer who brutally raped and bashed him.
After a stint on Hamilton Island as an apprentice chef, Purtill refined his hospitality skills around Sydney before opening a restaurant in Byron Bay.
It was there he developed a dependence on alcohol and hard drugs.
Evidence tendered in court suggested that on the day Mr Garda was murdered, he was given $86,000 worth of cocaine but no trace of the drug was found in Purtill's home.
Justice Harrison accepted Purtill's troubled history but found there were no special circumstances impacting his decision as there had been no evidence of provocation and he was satisfied Purtill remained "wholly unremorseful".
Purtill was given a head sentence of 28 years.
He will be eligible for parole on February 26, 2031.