A man with a disability was murdered hours after he disclosed his pin in order to buy an iced coffee, a court has heard.
A teenager who shot a sleeping disabled man in the head in order to steal his Centrelink payments said he came up with the idea after he was asked to purchase the victim an iced coffee.
The 32-year-old killer, who cannot be named because he was 16 at the time of the murder, went on to siphon thousands of dollars while telling others the victim, Martin Meffert, had “gone back to Adelaide”.
Mr Meffert was aged 23 when he was last seen alive in 2005, but the man was not charged with his murder until 2018.
Handing him a 20-year non-parole period in the Supreme Court on Tuesday, Justice David Peek said the murder took place in February or March.
He said, in the days leading up the murder, the pair had spent time together at Mr Meffert’s home in Terowie, in the state’s Mid-North.
“On the day of the murder, you say that you had been taking illicit drugs, but the deceased had not been, and nor had he been drinking alcohol with you,” Justice Peek said.
“You say that, in the evening, you smoked some cones of cannabis, had something to eat, and that the deceased watched television in the lounge room.
“You say that the idea of murdering the deceased first arose earlier that day when he asked you to purchase an iced coffee from a local shop using his key card and he gave you his PIN.”
Mr Meffert was receiving a disability support pension after he was diagnosed with attention deficit disorder a few years prior.
In October 2013, more than eight years after Mr Meffert’s death, police found some of his remains in a bag at his killer’s home at Terowie.
Further remains were found in the backyard of the home in August 2019.
The man was charged with murder in September 2018 and later pleaded guilty.
He told police he fetched a bolt-action rifle after Mr Meffert had fallen asleep on the night of the killing, before he fired a fatal shot from outside the house.
Justice Peek rejected parts of his account and said the man admitted the murder was “pre-planned”.
“You wanted to thereby finance your expensive drug habit and general living expenses,” he said.
The court has previously heard about $130,000 was withdrawn from Mr Meffert’s bank account through ATMs in the Mid-North.
The killer will be eligible for parole in 2038.