Accused killer's clothes dumped near car

After grocer Paul Virgona was gunned down on a Melbourne freeway while on his way to collect fruit and veg, two offenders were seen fleeing from a getaway vehicle.

Two bags of clothes were dumped by one of the killers as police took chase.

Clothes in one belonged to accused killer Aaron Ong.

But to think it must be because he was one of the killers is a seductive and simplistic way to view the case, Ong's barrister Mark Gumbleton told the jury in his murder trial on Tuesday.

"If it was that simple I wouldn't be here," he said.

Ong and another man, Josh Rider, are charged with murdering Mr Virgona, who was shot at 11 times while driving his white van on the Eastlink freeway just after 2am on November 9, 2019.

Seven bullets from a semi-automatic handgun struck him. The 46-year-old died from blood loss at the scene.

Rider's murder case is being run separately.

"The evidence is really good that (Rider) was one of the two offenders," Dr Gumbleton told jurors.

"That's how I intend to close ... that one of the two was Rider, but you couldn't be satisfied that Ong was the other fellow."

Prosecutor Mark Gibson alleged Rider and Ong, who are both associated with a motorcycle club, had been together at the club's Port Melbourne premises in the hours before the shooting.

It's alleged the two men watched Mr Virgona's Croydon home for two hours before following him when he left for work, bound for the Epping markets, at about 2am.

"There was nothing in Mr Virgona's background that explained why he was targeted and killed," he said.

Prosecutors also can't say if it was Ong or Rider who fired the fatal shots.

"One was driving and one was shooting," Mr Gibson told the jury in his opening statement, which began Monday and continued Tuesday.

The prosecution case is that each was complicit in Mr Virgona's murder, having a joint intention to kill or really seriously injure him.

Dr Gumbleton didn't dispute that there were two men in the car, or that Ong and Rider were associated.

But the criminal justice system isn't based on guilt by association, he said.

"Our defence is that Ong was not either of the two people in the Mercedes at the time the weapon was discharged," he said.

It's alleged that after the shooting Ong and Rider returned to a Mooroolbark property where they had stored a getaway car.

Police tried to intercept that vehicle about an hour after the shooting and were led on a high-speed chase.

Two people fled the vehicle into Bayswater Park after crashing into a give way sign.

The gun used to kill Mr Virgona has never been found.

The trial continues on Wednesday