A father has admitted he gunned down another man in a suburban street but says it was a clumsy accident.

But they denied he committed murder, arguing Picking did not mean to pull the trigger and he should instead be found guilty of manslaughter.

“What happened here was a warning that went wrong,” Picking’s barrister Peter Morrissey SC told the jury today.

Prosecutors allege Picking and his son Brodi, 19, ambushed Jemal outside a Glenroy shopping strip in Melbourne’s north about 4.30am on March 29.

Brodi, who is also on trial for murder, knew Jemal but the pair had a falling out in early March after Brodi accused the 33-year-old of stealing his wallet.

Prosecutors allege in the hour before the shooting, Brodi and Luke Picking drove past locations connected to Jemal, including his mother’s home.

It’s alleged they located Jemal driving a red Hyundai in Glenroy and followed the 33-year-old until he pulled over and confronted them.

CCTV footage played to the jury showed yelling between the two groups before Jemal was shot in the face.

Prosecutors allege Luke Picking said “you want a f—ing air raid” to Jemal before firing the bullet and speeding off.

Jemal stumbled back to his car and managed to press down on the horn before he collapsed.

He died after suffering multiple shotgun pellets to the face and neck.

Morrissey told the jury Luke Picking was responsible for Jemal’s death and had already offered a plea to manslaughter, which prosecutors rejected.

The barrister argued Picking had only intended to threaten Jemal and it went wrong.

“He did mean to present the gun … but he didn’t mean to pull the trigger,” Morrissey told the jury.

Morrissey said there would be evidence from a neurologist, who had identified issues with Picking’s hands that caused him to be clumsy.

Brodi Picking’s barrister Rishi Nathwani KC conceded his client was in the car when Luke fired the fatal shot. 

But he told the jury Brodi did not know there was a loaded gun in the vehicle and he never made an agreement with his father to murder Jemal.

“He did not positively assist or encourage his dad to do so,” Nathwani said.

It was also disputed that Brodi was still upset about the stolen wallet at the time of the shooting, the barrister said.

Prosecutors allege after the killing, Luke Picking contacted his friend Ian Harris, 49, to dispose of the gun.

Harris’ barrister Rahmin de Kretser accepted his client did take possession of the firearm but argued Harris did not know it had been used to kill someone.

de Kretser told the jury they should have great doubts his client was guilty of assisting an alleged murderer.

The trial before Justice Jane Dixon continues.