After shooting his friend in a drug deal gone wrong, Norden Wilio pulled the trigger again and fatally shot the man they had intended to rob.
Ali Ali, 28, had been involved in a scuffle with cannabis dealer, 40-year-old Deniz Hasan, before he was shot by Wilio in the Melbourne suburb of Meadow Heights in March 2019.
After seeing "pounds" of marijuana in the boot of Mr Hasan's car, Mr Ali told him he was heading home to get cash.
He instead returned with Wilio, who was armed with a shotgun.
Mr Hasan tried to flee when he saw the weapon but his attempted robbers dragged him from the car.
Admid the scuffle, Wilio fired the weapon the first time.
A witness who lived on the suburban street heard the shot fired and looked out her window.
She saw a silhouette with a shotgun, raised at waist-height, and watched as he fired it again. Mr Hasan was struck and killed.
Wilio put his friend in a shopping trolley and was captured on CCTV wheeling him away from the scene. Mr Ali later died.
A jury found Wilio, 26, guilty of murdering both men.
Mr Hasan's sister said words couldn't describe what her family had been through since the "horrific act of violence" that claimed her brother's life.
He was a father of two young girls, she said.
In a pre-sentence hearing, Justice Andrew Tinney speculated that Wilio's effort to leave the scene with Mr Ali in a shopping trolley was an attempt to put some distance between them and his second victim.
But Peter Chadwick, for Wilio, said if his motive had simply been to get away he could have melted into the night through a nearby park.
"It was Mr Ali who was heard to say 'let's go' or words to that effect," he added.
Justice Tinney added that it was hard to view the shooting of Mr Hasan, after the shooting of Mr Ali, as "anything other than gratuitous".
"He already knew his friend had been shot, and some seconds had passed before he made the decision to pull the trigger and shoot Mr Hasan," he said.
The gun has never been found.
Justice Tinney said it would be difficult to impose a prison sentence on Wilio that would not seem crushing to a 26-year-old.
The pre-sentence hearing will continue at a later date.
