The case gained popularity due to the success of The Teacher’s Pet, a true crime podcast that focused on the case.
The podcast was removed due to impeding court proceedings.
Lynette Dawson, a mother of two vanished from Sydney’s Northern Beaches in January 1982.
Her husband Chris was adamant she ran away and has since pleaded not guilty to her murder.
Lynette has never been found and it has long been suspected that Chris was involved in her disappearances.
He was first arrested in December 2018 and accused of murdering his wife so that he could have a relationship with his then teenage babysitter known only as JC.
During the trial, it was revealed that JC had moved in with Chris just days after Lynette’s disappearance before marrying the former high school teacher in 1984.
The couple separated in 1990.
On Tuesday, Justice Harrison announced that he had found Chris guilty of murder, rejecting the possibility that Lynette abandoned her family and vanished.
Watch Below: Chris Dawson confronted over wife Lyn's disappearance
“I am satisfied beyond reasonable doubt that the phone call material and the sightings evidence do not establish that Lynette Dawson was alive in circumstances to which they separately relate,” Justice Harrsion said today.
“I’m satisfied that none of the alleged sightings was a genuine sighting of Lynette Dawson.
“My conclusions in that respect have in the first instance been based upon the incidents considered individually.
“The whole of the evidence satisfies me that Lynette Dawson is dead, that she died on or about 8 January 1982 and that she did not voluntarily abandon her home.”
Nine News reporter Tiffiny Genders, who attended the verdict revealed the moment Lynette’s family heard the guilty verdict, sharing on social media:
“Lyn’s family was a metre away from #Dawson in court as he learnt his fate, they are clutching each other’s hands & gasped as he was led away.”
“They never thought this day would come but their 40 year old suspicions have been confirmed.”