Dawson will be eligible for parole after 18 years. He would be 92.
“I recognise that the unavoidable prospect is that Mr Dawson will probably die in jail,” Harrison noted.
Harrison said Dawson’s crime was inspired by an “uncontrollable desire” to be with his high school student and family babysitter, known during court proceedings as JC.
He said the murder was neither “spontaneous” nor “unavoidable”.
“The fact Lynette Dawson’s body has never been recovered is an aggravating circumstance of the murder,” Harrison said.
“Murder is uncontroversially a serious crime.
“In my opinion, the murder of Lynette Dawson is an objectively serious crime.”
Lynette was “faultless” and “undeserving of her fate”, Harrison said.
Harrison said the evidence does not reveal whether Dawson committed the crime by himself or with assistance.
But he said Lynette was murdered at the family home in January 1982.
“The evidence does not reveal how Dawson killed Lynette Dawson. The evidence does not reveal where Lynette’s body is now,” Harrison said.
Harrison said Dawson continues to maintain his innocence and shows no remorse for his crime.
Harrison said Dawson has enjoyed decades of freedom and referenced the 74-year-old going on to marry and have a child with JC.
“His denial of responsibility for that crime has benefited him in obvious ways,” he said.
In deciding the sentence, Harrison said the media attention of the case, which Dawson’s lawyers argued should be a mitigating factor, was a consideration however in the end the 74-year-old was the “author of his own misfortune”.
“Dawson’s crime is a matter of intense public interest,” Harrison said.
“His major complaint, when properly understood, is that the publicity improperly made assumptions about his guilt at a time when he was entitled to the presumption of innocence.”
Ultimately, Harrison said a “just and appropriate” sentence needed to recognise the “human dignity of the victim of domestic violence and the legitimate interest of the general community in denunciation and punishment of someone who kills his spouse”.
Dawson has filed an appeal of his conviction.
Dawson’s lawyer Greg Walsh said outside court Harrison’s sentence was a “reasonable judgement”.
”There are no winners in a tragic case like this. Lynette’s family have lost their daughter, sister, mother and the extended family has suffered,” Walsh said.
“The reality is he knows he will spend in the rest of his days in jail unless he is successful on his appeal.”
Walsh said Dawson continues to maintain his innocence and refuses to reveal where Lynette’s body was disposed.
He added Dawson is being referred to as “the Teacher’s Pet” in prison, the name of The Australian’s podcast that detailed his crime.
“He’ll live with that irony for the rest of his days,” Walsh said.