Rodney Phillips, 25, of Oak Park, and Sam Liszczak​, 23, of Morwell, are accused of fire-bombing homes, shooting at crime figure George Williams' house, stealing a car and shooting at a police officer, Constable Ben Ashmole.

Constable Ashmole required surgery to remove shotgun pellets from his skull.

Mr Phillips and Mr Liszczak on Thursday formally pleaded not guilty to the crime spree, both telling the Melbourne Magistrates' Court they were innocent of all the charges.

The pair were kept under heavy guard during their four-day committal hearing, with six officers from Corrections Victoria's Security and Emergency Services Group flanking them throughout proceedings.

Mr Phillips regularly removed his long-sleeved T-shirts in the dock to display his singlet and multiple tattoos, and the pair shook hands and embraced when they were committed to stand trial in the Supreme Court for the attempted murder of Constable Ashmole.

Police allege the pair packed a car full of empty Corona bottles that they had turned into Molotov cocktails, on Saturday July 5, 2015.

Perhaps unfortunately for them, police allege that they had taken Phillips' twin brother's car, which was fitted with an alcohol interlock device that intermittently takes photos of the driver.

The pair are alleged to have hurled a dozen Molotov cocktails at homes in Broadmeadows and Pascoe Vale, in the same streets as the former wife of slain gangland criminal Carl Williams and his now-deceased father, George.

Two days later, police allege, the pair stole a car in Endeavour Hills – it too was photographed when the driver ran a red light, according to a police summary released by the court.

It's claimed the pair drove the stolen car to George Williams' home and unloaded a couple of shotgun blasts into the fence.

When they drove to Ms Williams' home, prosecutor Neill Hutton said, they were spotted by a police car waiting for them, which pursued the pair.

The police managed to corner the car at St Monica's Primary School in Pascoe Vale, but as the stolen vehicle turned to escape, a shotgun was pointed through the passenger side window and into the police car's open drivers' window, the court was told.

Constable Ashmole managed to turn and duck as he saw the shotgun coming through the window, probably saving his life, according to police.

"The only thing that was going to stop the two men was for the driver of the police car to be shot and killed," Mr Hutton said.

But defence lawyer David Hallowes​ told the court that police could not prove that Mr Liszczak was guilty of attempting to murder Constable Ashmole,.

Either of the accused men could have been driving the car, Mr Hallowes said, and therefore either man could have discharged the gun.

"For my client to be guilty in circumstances where it can't be proved that he was the one that discharged the firearm, it has to be proven that he knew," Mr Hallowes said.

He said that for police to prove the attempted murder charge, they would also have to prove that Mr Liszczak knew the gun was going to be fired in Constable Ashmole's face, and that he had a "reasonable expectation" that this would kill the policeman.

Mr Phillip's lawyer Stewart Bayles said the same defence would apply for his client.

A directions hearing will be held on July 4 at the Supreme Court.