Lynette's family make final plea to public after Chris Dawson sentence

Greg Simms is reclaiming his murdered sister's name.

After watching her murderer being told he would "probably" spend the rest of his life in prison, Mr Simms asked for one final act.

Chris Dawson was found guilty of killing his first wife, Lynette, earlier this year and was jailed for a maximum 24 years yesterday.

The case received international attention when the podcast The Teacher's Pet was released in 2018.

Since then, the name Lynette Dawson has been in the public spotlight again, but Mr Simms wants that to change.

"Chris Dawson discarded her. The Dawsons disregarded her," he said on the steps of the Supreme Court in Sydney.

Justice Ian Harrison found Dawson murdered Lynette Simms in 1982 after lawyersargued it was to have an "unfettered relationship" with the family's 16-year-old babysitter, referred to in court as JC, who he later married.

Lynette went missing from her Bayview home, on Sydney's northern beaches, on January 8. She was 33 at the time.

In handing down his sentence, Justice Harrison called Dawson's crime "self-indulgent brutality".

"Tragically her death deprived her young daughters of their mother, so that was a significant part of the harm caused to others, and by inference to the community, as a consequence of her death," he said.

"[She] was treated by her husband, the father of the very same girls, as completely dispensable."

Mr Simms and Lynette's childhood friend Carol Field commended the judge on the length of the sentence.

"I hope Chris Dawson lives a long life in order to serve that sentence," Mr Simms said.

"No sentence is long enough for taking someone else's life," Ms Field said.

"He may not live for 24 years, but I hope he lives for quite a long time."

The family can now begin living their lives again, but it's not the end of Lynette's story. 

"Chris Dawson has had 40 years of freedom. Now, it's our turn," Mr Simms said. 

"What we need now is to find Lyn and put her to rest."

NSW enacted "no body, no parole" legislation in October, gaining traction following Dawson's conviction.

It means Dawson won't be granted parole in 2040, unless the State Parole Authority is satisfied he has cooperated in disclosing Lynette's whereabouts.

At 74 years old, Justice Harrison said it is likely that Dawson will die in jail.

He will be 92 years old when he is eligible for parole in 18 years time.

Dawson's eldest daughter Shanelle begged her father to "admit the truth" about where her mother is during her Supreme Court victim's impact statement in early November.

"I hope you will finally admit the truth to yourself and give us the closure we need," she said.

Justice Harrison said many questions still remain.

"The evidence does not reveal how Mr Dawson killed Lynette," he said.

"It does not reveal whether he did so with the assistance of anyone else or by himself. It does not reveal precisely when he did so. The evidence does not reveal where Lynette Dawson's [Simms] body is now."

It is a fact that will remain with Dawson while he lives out his life behind bars.