A coroner has recommended a New South Wales doctor be banned from performing autopsies after handing down a scathing assessment of a post mortem examination he performed.

Deputy state coroner Helen Barry was investigating the death of 49-year-old Bradley Miller whose body was discovered on the banks of the Murray River in Victoria in May 2013.

Part of her investigation was looking at the autopsy performed by medical officer Dr Peter Robinson.

She was scathing in her findings, saying he was not a coronial medical officer and under NSW Health policy guidelines he was meant to consult with a specialist forensic officer.

"Dr Robinson failed to do this and it is not clear from his oral evidence that he was aware of these guidelines," Ms Barry said.

She was also highly critical of the two reports he compiled on Mr Miller's body.

Doctor listed autopsy date before death

"Not only do they fail to contain the level of detail to be expected from a professional, it is clear that Dr Robinson was simply filing in a template and recorded his 'findings' in a cut and paste form," she said.

"In his first report, the date listed for the autopsy is 3 January 2013, more than four months prior to Bradley's death.

"In his second report, Doctor Robinson described conducting an internal examination of the dead body of a female."

She concluded the autopsy had an effect on determining the cause of death.

"Regrettably, the quality of the autopsy conducted by Doctor Robinson was so poor that it resulted in a loss of quality evidence that may have delivered some certainty to the cause and manner of Bradley Miller's death, and consequently some much desired answers for the family members," Ms Barry said.

"It is disturbing that Dr Robinson, in his oral evidence, advised that he was still conducting autopsies.

"This is clearly unacceptable and inappropriate.

"I recommend that consideration be given to Dr Peter Robinson not being accredited as a coronial medical officer to undertake any post mortem examination of any kind."

The inquest was also examining whether Mr Miller took his own life, given a number of purchases he made before he died, and he had previously discussed suicide with a friend.

Toxicology results detected small quantities of alcohol and ibuprofen in his blood.

Coroner not satisfied Miller took his own life

But Ms Barry said, given the level of decomposition, these results must be interpreted cautiously.

"No assistance can be gained from these results which would shine light onto Bradley's state of mind at the time of ingestion," she said.

"There was no evidence of his planning to take his life and there was no such communication to any family member.

"A finding of suicide is a serious finding and there must be clear cogent proof on which to base a finding. I am not satisfied ... that Bradley Miller intentionally took his own life."

Dr Robinson has been contacted for comment, as has the NSW Minister for Health.