A then-teenager who fatally shot a man in a tragic case of mistaken identity has been sentenced for his role in a Civic brawl said to have terrified onlookers a year later.
In sentencing the now 20-year-old for his latest crime, special magistrate Sean Richter described him as: "A young man who has found himself at the top end of the criminal world at a very young age."
The offender cannot be named because he was only 17 when he killed 48-year-old Glenn Walewicz at his Phillip home in mid-2021 with a .22 pump-action rifle.
In May, the offender received a 13-year jail term for the "botched home invasion" murder and will serve seven years and nine months behind bars as a result.
On Tuesday, he faced the ACT Magistrates Court after being found guilty of affray relating to a separate Garema Place incident in May 2022, when he was aged 18.
The court previously heard details of the public fight during a hearing to determine the then-teenager's guilt.
He was accused of being part of an "aggressor group" acting violently towards "random members of the public throughout the night".
"It's fortunate no one was badly injured," Mr Richter said.
While the magistrate did not elaborate on his findings about evidence heard last year, a police officer previously told the court he saw the offender tackle a man and kick him in the head twice.
On Tuesday, a prosecutor said the night in question had caused an onlooker to fear she would be assaulted and described another witness as "horrified" during the incident.
The offender was involved in the brawl about a month before being arrested for Mr Walewicz's death.
"He had committed a serious of murder and was aware that someone had died because of his actions," the prosecutor said.
Legal Aid lawyer Sam Brown said his client has experienced a period of psychological turmoil and increased drug use following the murder.
Mr Brown also described the offender as having had a "complex childhood", resulting in significant trauma and mental health challenges.
The magistrate agreed the 20-year-old had a "tragic upbringing" but said he felt optimistic for the convicted killer, who told the court he would seek a trade once transferred to Canberra's adult prison later this year.
The offender was given a four-month jail term for his affray charge, backdated to July last year to be effectively already served as concurrent with his murder sentence.
"Good luck, young man," Mr Richter told him.
