A former Australian high school teacher convicted of murdering his wife after a hit podcast unearthed new evidence has been sentenced to 24 years in prison.

Chris Dawson, 74, was convicted earlier this year of killing Lynette Dawson some 40 years ago, while pursuing an affair with his teenage babysitter and former student.

Her body was never found and there were few leads in the case until 2018 when 'The Teacher's Pet' podcast sparked renewed public interest and ultimately a fresh police investigation.

The murder had been driven by Dawson's "possessive infatuation" with his former student, which led him to kill his wife, Judge Ian Harrison said today while announcing the 24-year prison sentence.

There is a non-parole period of 18 years.

'The Teacher's Pet', hosted by Hedley Thomas (above), sparked a fresh police investigation

"Mr Dawson is not old by contemporary standards, but he will not live to reach the end of his non-parole period," the judge said.

Dawson strenuously maintained his innocence throughout the trial.

'The Teacher's Pet' was hosted by journalist Hedley Thomas, and a few months after its first episodes were released, Dawson was arrested in December 2018.

It drew comparisons to the genre-defining 'Serial' podcast in the United States, which played a pivotal role in overturning a man's conviction for murdering his girlfriend.

Greg Simms, Lynette Dawson's brother, and his wife Merilyn speak to the media outside court

Lynette Dawson's brother, Greg Simms, thanked Mr Thomas.

"My hope is that the media and police will work collaboratively in future cases," Mr Simms said outside the court following the sentencing.

"It's our time to begin living our lives without having this hanging over our heads."