An Olympic boxing hopeful accused of murdering an innocent man was not at the scene of the crime as he was cleaning up his home after it had been firebombed, a court has been told.
Musa Alzuain was 19 years old when he allegedly shot panel beater Jason De Ieso at point blank range with a sawn-off shotgun at his business in Pooraka, northern Adelaide, in November 2012.
Alzuain, now 30, is the youngest of eight men with links to the Hells Angels motorcycle gang on trial in the South Australian Supreme Court for Mr De Ieso's murder.
Accused alongside Musa are his brothers Husain Alzuain, 35, and Mohamed Alzuain, 32, as well as Daniel Mark Jalleh, 34, Ross William Montgomery, 38, Seywan Moradi, 36, Kyle Lloyd Pryde, 35, and Nicholas Sianis, 36.
All have pleaded not guilty.
A ninth man suspected of taking part in the attack has since died.
The jury has previously heard the group, brandishing firearms and concealed in hoodies and masks, stormed Mr De Ieso's shop in broad daylight, intending to kill a different man who was a rival member of the Finks bikie gang.
But they arrived minutes after their target had left and instead opened fire on Mr De Ieso.
Musa Alzuain, a close associate of the Hells Angels at the time, was in the middle of an escalating conflict between the two gangs, which culminated in his family home being firebombed the day before the shooting.
His lawyer, Andrew Fowler-Walker, denied he was present at the shooting and was instead at home that day with his brother Husain, cleaning up the damage from the firebombing.
Crown prosecutor Jim Pearce KC earlier compared CCTV footage of the crime scene with separate footage of Musa Alzuain, which he claimed proved he was present at the scene.
Although the figure's face was obscured by his hoodie, Mr Pearce claimed there were similarities to Alzuain's chin, lips and imposing physique.
Mr Fowler-Walker said the comparison was "fraught with danger", given the quality of the CCTV footage.
"There is no evidence in this trial of direct identification or recognition evidence," he said.
Mr Fowler-Walker urged the jury to reject the testimony of a key witness for the prosecution as "dishonest, unreliable and self-interested" and to cast aside any prejudice they may hold against Musa Alzuain for his connection to the Hells Angels.
"The fact is that there is an innocent man deceased, Mr De Ieso," he said.
"It is tragic and you might feel huge pressure to convict whoever is charged because of that fact alone, but that would be quite unfair.
"It takes courage to maintain the integrity of our justice system. You don't convict people if you have a reasonable doubt about their guilt.
"Keep your feet firmly on the ground when you assess the evidence in this case."
Musa Alzuain never followed through with joining the Hells Angels as he was still hopeful of qualifying for the Olympics as a boxer, the jury heard.
Mr Fowler-Walker will resume his closing address on Monday.
