Did someone else kill Shaun Barker?
GOLD Coast father Shaun Barker was kidnapped from a servo, taken to Gympie, tortured for days, murdered with a hammer and his body destroyed in a forest fire pit around six years ago.
Three men were convicted over Mr Barker's death but now one of those killers is claiming police let the real culprit walk.
William Francis Dean is serving a life sentence for the kidnapping, torture and murder of Mr Barker, who was last seen alive in December of 2013.
The 33-year-old's remains were found in a Gympie forest in April of 2014.
Dean's co-accused Stephen John Armitage and Matthew Leslie Armitage were both convicted of Mr Barker's murder but this was downgraded to manslaughter on appeal.
The father and son's convictions on torture were overturned and a new trial ordered.
Dean is appealing his convictions, claiming he is innocent and another man was responsible for the gruesome killing.
At Dean's trial, a jury heard CCTV captured Mr Barker being led into a car by two men at a Broadbeach service station around the time he disappeared.
Cameras on the Westgate Bridge captured Dean's vehicle crossing over shortly after, but the images did not show anyone in the back seat of the vehicle.
The jury also heard evidence of Mr Barker was kept in one of Stephen Armitage's commercial fishing eskies, that he was denied food and water, that he was tied to a tree and repeatedly beaten with a hammer.
It was also alleged his bones were broken and his genitals were covered in honey to attract ants.
Dean was said to have been the person who disposed of Mr Barker's body by burning him in a firepit in the forest where the victim's remains were found.
Facing the Queensland Court of Appeal on Friday, Dean claimed police "manipulated" evidence to prove their case against him and the other men.
He claimed that another man confessed to killing Mr Barker and that an investigating detective had noted this down but the evidence was never put to the jury.
"There was an audio recording of police when he (the other man) was accused of bashing his missus," Dean told the three CoA justices.
"He says how he was there when Shaun Barker was bashed to death with a hammer and his face was smashed in."
Dean also demanded the appeal court have items located in the area where Mr Barker's remains were found tested for DNA, saying this would prove he was never there.
Dean told the justices that the witnesses were not cross examined properly at trial.
The Court of Appeal was also asked to consider whether or not the jury erred when it convicted Dean of murder because the use of a hammer to cause grievous bodily harm did not automatically mean there there was an "intent" to kill.
The Crown has opposed this, saying the intent of the three men was to torture Mr Barker until he gave them the information they were seeking and that when he refused to speak they crossed the point of no return and had to kill him.
The Court of Appeal has reserved its judgment and will deliver its decision on a date to be determined.