Frank Abbott said police were looking in the "wrong spot" for William Tyrrell and told locals he'd smelt something "like a dead human" in bushland near Kendall in NSW, an inquest has heard.
The prisoner's history has been scrutinised in recent days at the inquest into the three-year-old boy's disappearance from the mid-north coast town in September 2014.
Abbott was acquitted in the early 1990s of the 1968 murder of a teenage girl in Sydney. He's currently serving time in Cessnock jail on an unrelated conviction.
The acquittal was a topic he'd "constantly go on about", local man Dean Anderson told the NSW Coroners Court on Thursday.
"He was constantly like 'I beat a charge of murder'," Mr Anderson said.
"(He'd bring it up) just in small talk, like a badge of honour."
Mr Anderson said Abbott made a strange comment when news broke that police investigating William's disappearance were searching the home of washing machine repairman Bill Spedding.
Mr Spedding has since been ruled out as a person of interest.
"Frank made a comment that he felt they were searching a wrong spot for William Tyrrell," Mr Anderson told the court on Thursday.
"It seemed to be a very strange comment to make."
Abbott, who is expected to give evidence from jail before the inquest closes on March 20, also repeatedly spoke of smelling something dead in bushland beside a road he walked along near Logans Crossing.
Mr Anderson told the court he suggested the smell was probably a dead kangaroo, to which the now-prisoner responded: "No, I know the difference between a dead kangaroo and a dead human smell."
"I said 'How would you know what a dead human smells like anyway?' He ended the conversation there," Mr Anderson said.
Eventually, the frustrated tradie told Abbott to "go to the police or shut up about it".
The inquest has heard that in about 2016 or 2017, Abbott complained he'd earlier driven a woman and a child to Tamworth and not been paid.
Antique dealer Elizabeth Rowley on Thursday said the former owner of a scrap metal business later approached her to speak about Abbott's past, telling her he may have "got off a murder" and he "may have been responsible for someone going missing before".
"Did Dooley tell you - based on those things and the timing of the trip to Tamworth - that it may be related to William's disappearance?" counsel assisting the coroner, Gerard Craddock SC, asked.
"Yes ... he wanted me to tell my husband," Ms Rowley replied, adding her husband was a police officer.
Abbott is among hundreds of "persons of interest" in the Tyrrell investigation. No one has ever been charged over the boy's disappearance.
The inquest is set to resume on Friday.
Australian Associated Press
