His son-in-law David Phillips told a family friend he killed Ball after claiming his father-in-law had sexually assaulted a girl, the coroner heard on Monday.
Brian Murphy said Phillips told him that he also killed another man and buried him with Ball in a bid to cover up the alleged murder.
At a re-opened inquest into Ball’s disappearance, Murphy said Phillips confessed to luring his father-in-law into the garage of his Townsville home before bashing him.
“When he got him out there he said ‘I bashed him unmercifully’,” Murphy told the inquest.
“He said: ‘I gave him such a thrashing, I had him by the throat up against the wall and all but got his windpipe out of his throat’.”
Phillips then claimed he went to a local hotel and found someone who “looked remarkably like his father-in-law” and brought him back to the house, Murphy said via phone link.
He said Phillips told him he recruited the lookalike so a neighbour who waved at everyone from her verandah “thought it was his father-in-law” when they went past.
Phillips then revealed the pair took the body away in a truck before he killed the lookalike and buried him with Ball, Murphy said.
“He said ‘I gave it to the old bloke and I buried the both of them … in the same grave … and then I took the truck to the railway station’,” Murphy told the inquest.
He first met Phillips when they were both Victoria Police officers in the 1980s.
He said Phillips relocated to Queensland and made the confession after they reconnected again in 1994 or 1995.
“I couldn’t believe that he was telling me. It was unsolicited. I don’t why he told me,” Murphy said.
After being re-opened at the direction of the attorney-general, coroner Stephanie Gallagher will consider whether Ball died and the identity of anyone involved in his disappearance or death.
The coroner at an inquest in the 1990s was unable to find Ball’s disappearance was due to foul play but said “the evidence indicated his absence was due to other than his own making”.
The inquest was closed but reviews were held and witnesses interviewed again.
It culminated in a report containing new findings that were submitted to the Coroners Court in May 2017.