Victoria Police didn't bother to investigate the officers who sprayed bullets at an erotic nightclub event, hitting two people and sparking a multi-million-dollar payout.
The force also did not reprimand any officers who opened fire in the busy nightclub at a man they had been told was only carrying a $2 plastic toy gun.
The failure has prompted a lashing from Victoria's Independent Broad-based Anti-corruption Commission.
"Victoria Police only investigated the conduct of the patrons involved in this incident, and not the actions and conduct of police officers," IBAC Commissioner Robert Redlich QC said on Thursday.
"Victoria Police has failed to assess the planning and actions of the police officers involved in this incident."
Deputy Commissioner Shane Patton said police were waiting for the civil lawsuit to finish before doing their own review, but Mr Redlich said that wasn't an excuse.
"That was not an appropriate reason for not undertaking the necessary review," Mr Redlich said.
Mr Patton promised police would finally run a review, more than two years after the shooting. He confirmed no officers had been reprimanded over the shooting.
"We will now launch, reopen our investigation in regards to the matter and determine if any new facts or circumstances that came out in the civil proceedings, or any other information that has came to light, justifies any further actions," he told reporters.
Mr Patton said the officers acted in "self-defence" but police would now investigate if that was actually the case.
Dale Ewins and former girlfriend Zita Sukys were dressed like punk icon Sid Vicious and a naughty schoolgirl at the Inflation nightclub's Saints and Sinners party in July 2017.
Heavily armed police stormed the venue after a patron reported Mr Ewins had a gun in his pants, and the pair were shot while performing a sex act.
Police had been told by staff at the club the gun was a fake before they opened fire, the Supreme Court was told.
Mr Ewins was shot twice in the back, tasered three times, beaten and stomped on, while Ms Sukys was shot in the leg.
He has emphatically denied ever pointing the toy gun at police, and CCTV footage is not conclusive.
Mr Ewins, Ms Sukys and Inflation nightclub owner Martha Tsamis agreed to a confidential settlement on Wednesday. It has been reported that the deal is worth more than $3 million.
Ms Sukys received an apology that she was an "innocent bystander who was injured through no fault of her own in the circumstances of the case".
Premier Daniel Andrews said he was not privy to the settlement details.
"It was very unfortunate. A real tragedy," he told reporters on Thursday.
Opposition Leader Michael O'Brien said taxpayers had the right to ask what had happened to their money.
Australian Associated Press