A heroin addict who fatally stabbed a Melbourne man in the back during an argument had a long drug and alcohol abuse history.
Sunshine North man Rasim Vikic will be sentenced next month over the murder of 31-year-old Leigh Graham, who suffered injuries to his upper body in a fight at a house in July last year.
His lawyer David Hallowes told the Victorian Supreme Court on Wednesday, his client was in the grips of heroin addiction at the time of the murder.
The plea hearing heard his reliance on substances ramped up when his twin brother died of an overdose in 1995, aged 17.
Mr Hallowes said Vikic had the support of his Bosnian parents, who had attended every day of the trial, but were not in court for Wednesday's hearing.
He said psychologists had found that Vikic had suffered from impulsivity and said that should be reflected in his sentence.
"In relation to the murder, I submit it was relatively spontaneous, he did not go there to commit murder," he said.
Crown Prosecutor Darryl Brown agreed the crime was "relatively spontaneous" and told Justice Paul Coghlan he believed sentencing "around the middle" would be fair considering he had armed himself with a knife.
Five victim impact statements were read to the court, including that of Mr Graham's 14-year-old daughter.
"Things went downhill for me, I stopped going to school, I started fighting with my family and was hanging around very bad people," his daughter told the Supreme Court on Wednesday, during a plea hearing.
"No matter how he lived his life, Leigh was my father. And when he was murdered my last hope of forming a relationship with him was taken away from me."
The court heard how the teen and her brother had both struggled since their father's murder - the girl admitting she turned to drugs and alcohol to try to escape reality.
Their mother Katie said they were now both back on track after changing schools, but their pain is still very real.
"Having a parent die when they are young is horrible but having them taken away by someone else's actions is unimaginable," she said during her victim impact statement.
Justice Coghlan will sentence Vikic on December 19.