By Jack Gramenz and Duncan Murray in Sydney

Chris Dawson will receive no reprieve from likely spending the rest of his life in prison after a failed bid to overturn his conviction for murdering his wife four decades ago.

A panel of three judges in the NSW Court of Criminal Appeal unanimously dismissed Dawson’s attempt to quash the guilty verdict on Thursday.

His lawyers had argued his trial judge made errors and there was not enough evidence to prove beyond reasonable doubt he killed his wife Lynette Dawson in 1982.

The state’s highest court upheld Dawson’s conviction, granting him leave but then dismissing his appeal.

While some errors in the decision from the judge-alone trial were identified, they were not significant enough to affect the outcome.

“No substantial miscarriage of justice has actually occurred as a result of the errors established,” Justice Christine Adamson said in the appeal court’s published reasons.

Prosecutors ran a compelling circumstantial case and Dawson’s “hypothesis consistent with innocence” was not reasonably open, the court ruled.

The ex-teacher and former rugby league player was convicted in August 2022 of murdering his wife so he could pursue a relationship with a teenage girl, who was one of his students.

Before then, Dawson began an affair with the student, sending letters referring to himself as “god” and threatening teenage boys he perceived as rivals.

He claimed he received a call from his wife on January 9, 1982, telling him she wanted time alone to think things over.

But the appeal judges supported trial judge Ian Harrison’s finding that Dawson lied about the call and had already murdered his wife by the time he said it took place.

Justice Anthony Payne said Justice Harrison’s failure to clearly distinguish between which lies were relied upon as evidence of Dawson’s consciousness of guilt and which were relevant to his credibility did not prevent the appeal court coming to the same conclusion.

“I am satisfied on all the evidence (Dawson) is guilty beyond reasonable doubt,” he said.

There was no possibility Dawson’s wife voluntarily left her children and then never spoke to her parents or siblings again, Justice Payne said.

Dawson was in a controlling relationship with a teenager he was obsessed with and prepared to take increasing risks to preserve it.

There was also abundant evidence showing Dawson knew his wife was not coming back.

“(He) conducted himself in a manner which was completely irreconcilable with any purported belief that the deceased might return to the marital home,” Justice Payne said.

He moved the teen into his family’s Bayview home once before his wife disappeared and again afterwards.

The loss of bank records Dawson said showed his wife was still alive failed to establish a forensic disadvantage due to the four-decade delay in him being brought to justice.

Dawson knew the records were important but did not keep them and could have made the relevant purchases himself, rendering them neutral as evidence, Justice Adamson said.

The 75-year-old has also been convicted of a historical charge of carnal knowledge as a teacher of a girl over 10 and under 17.

He swore repeatedly when a judge delivered that guilty verdict in June 2023, which he also plans to appeal.

It added another year to the period before which Dawson will be eligible for parole.

His first possible release date will be in August 2041, when he will be 93.

Dawson’s full 24-year sentence for murdering his wife expires in 2046.

Her body has never been found and laws preventing parole in those circumstances mean he will likely spend the remainder of his life in prison.