An earlier police internal investigation found Officer A acted in self-defence.
A report by the Independent Police Conduct Authority (IPCA) backed the self-defence finding, but found that Officer A broke procedure by not telling other officers he was armed or at the shooting scene.
The coroner's report said Mr Bellingham had taken party pills and was "clearly not his normal self" on the night he smashed up his flat, his van and then took to the streets and asked people sitting in their cars for use of their vehicles.
When confronted on the street in the Christchurch suburb of Avonside, Mr Bellingham was hit by two shots from Officer A's Glock pistol and died at the scene.
Mr Shortland added that it was "entirely realistic there would be different outcomes" if another police officer, with their own experiences, had been placed in the same circumstances.
Ray Bellingham told the Weekend Herald his family had considered what happened, and the information they had about Officer A.
"We are convinced that if any other police officer had arrived at the scene, our son would still be alive. You don't shoot a guy with a hammer."
If Officer A had waited for the support of two other officers who arrived soon after the shooting, the outcome would also have been entirely different, Ray Bellingham said.
When spoken to by the Weekend Herald, Officer A said only that he wanted to pass on his respects to the Bellingham family. He would not discuss the coroner's report.
Ray Bellingham said his family had turned down the opportunity to meet Officer A after getting a card from him.
"I thought, 'What's the point?' I wouldn't have lost it or anything, but I would have got angry with him, and probably a lot of the questions he wouldn't have answered anyhow."
The coroner said he supported a system now in place whereby Officer A, as field supervisor, would have been required to advise colleagues of the decisions he was making at the scene.
