A teenager who fatally stabbed a father at a train station in Melbourne's outer suburbs says he has no recollection of the deadly attack.
The 19-year-old, who was 17 at the time of the stabbing, was drunk and potentially on drugs when he approached 40-year-old Adam Cassar at Melton train station in the early hours of December 29, 2021.
Mr Cassar appeared to be in the middle of changing clothes before the teenager followed him with a large knife and stabbed him, leaving him with a 10-centimetre wound.
The 40-year-old ran off and made it to a nearby house where he ultimately bled to death, while the teenager appeared none the wiser about the man's death and left the station with a group of boys, a Victorian court was told on Monday.
The teenager had no recollection of the attack because he was affected by alcohol and likely drugs at the time, his barrister said.
"We have no instructions, because he has no memory," the barrister told the court.
The teenager - who cannot be identified because he was underage at the time of the stabbing - came from his home in NSW to Melbourne in December 2021 to visit his mother.
The pair had a fractured relationship given she had abandoned her son, and whatever he hoped to get out of their meeting didn't eventuate, the teenager's barrister said.
Instead, he "wrote himself off then wound up at the station" before stabbing the stranger for an unclear reason and looking for a way back to his mother's home.
The teenager was extradited from NSW to Victoria, where he was in May this year found guilty of manslaughter.
Mr Cassar's daughter, who lives interstate, said she and her father didn't always see eye to eye, but his killer took away his chance to make things right.
In a victim impact statement she read to the court, she described the teenager as heartless and said she didn't think she would make it to court years after her father's death as she struggled with depression, anxiety and suicidal thoughts.
"He stripped away my dad's opportunities of finding love, meeting my future children one day and even seeing me get married," she told the court.
"I don't think any mother should have to help their child bury their father when they're 20 years' old."
The now 22-year-old started studying mental health before her father's death in a bid to ultimately help people like him, but struggled to continue with the course in the wake of his killing, she said.
Mr Cassar's father also required full-time care after his son's death.
The teenager's barrister said the 19-year-old's feelings of abandonment led him to use alcohol and drugs, and his recent diagnosis of ADHD went some way to explaining his impulsive decision making.
A judge is due to sentence the teenager later this month.
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