Mark Peckham has pleaded not guilty to murdering drug dealer George Kirk during a scuffle at a house in Dubbo, western NSW, in the early hours of August 16, 2023.
Peckham will argue that he acted in self-defence and did not inflict any wound that killed or badly injured Mr Kirk.
The first day of Peckham's NSW Supreme Court trial was told he knocked on Mr Kirk's bedroom window late on August 15 looking for drugs, but left after being told there were none in the house.
Just after midnight, Peckham returned with another man, Daniel Fitton, who accused Mr Kirk of "treating them like gronks", crown prosecutor Mark Hay told the jury.
Mr Kirk's girlfriend Tammy Antaw is expected to tell the jury she woke to a "commotion" in their bedroom and Mr Fitton pushed Mr Kirk into a table, Mr Hay said.
The prosecutor said Mr Kirk got up and began throwing punches, and Mr Fitton left.
The jury will hear evidence Peckham and Mr Kirk then began to push and shove each other, while Ms Antaw went to another room for help.
"She saw Mark Peckham stab George Kirk twice," Mr Hay told the jury at Orange courthouse on Thursday.
"She heard him hand to Mr Kirk a towel of some description, tell him to apply pressure and she heard Mark Peckham say sorry."
Peckham left the house, later telling a relative he stabbed a man who "came at him" during a fight, Mr Hay said.
Mr Kirk suffered three stab injuries, but died from a wound that penetrated his left lung.
The crown case was that Peckham was responsible for the fatal wound or, in the alternative, that he and Mr Fitton were part of a joint criminal enterprise and had agreed to violently rob Mr Kirk.
The jury also had the option of finding Peckham guilty of manslaughter, Mr Hay said.
The jury was told they should not speculate about Mr Fitton and it was only Peckham on trial.
Peckham's defence barrister James Trevallion SC said his client was "in the background" of the initial scuffle and was nowhere near Mr Kirk when he began bleeding profusely.
He only became involved in the fight when Mr Kirk, a larger man, began attacking him, Mr Trevallion said.
"The defence says George Kirk was over the top of Mark Peckham and ... his actions from there on are self-defence," he said.
"He doesn't cause any significant or fatal injury to George Kirk."
The trial continues before Justice Nicholas Chen
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