Joanne Curtis Believed Chris Dawson Killed His Wife: Friend

"She genuinely believed he killed Lyn, there's no doubt about it."

Joanne Curtis is known for marrying suspected murderer Chris Dawson when she was a teenager.

But Curtis' school friend, Michelle Walsh, believes she left Dawson because she knew he had killed his wife Lyn, who went missing from Sydney's northern beaches in 1982.

"She genuinely believed he killed Lyn, there's no doubt about it," Walsh told A Current Affair.

Michelle Walsh. Image: A Current Affair, Nine Network

Walsh claimed Curtis told police she believed Dawson had murdered his 33-year-old wife, and was "scared" after their relationship had ended.

"The way she spoke, she was really damaged," Walsh said.

At the time of Lyn's disappearance, Chris Dawson taught at Cromer High School, where Joanne Curtis was a 16-year-old pupil.  It was no secret within the school community that teachers were having sexual relationships with students.

A former student at the school herself, Walsh remembers watching Dawson seducing students, in particular Curtis.

"I was in the office, with Jo [Joanne] sitting on Chris' lap, there was no secret," she said.

Sydney couple Chris Dawson and Lyn Dawson (nee Simms) married in 1970 when they were both 21 years old. Image: The Teacher's Pet

"Mr Dawson didn't feel that he needed to hide it from me. We all knew they were in a relationship. We knew that she was Chris' girlfriend."

A teenager herself, Walsh said she wasn't immune to Chris Dawson's charms, and believes he was trying to groom her as well.

"I feel that I had about him, when I look at how I felt in his company, and how comfortable I was," she said.

The story of Lyn's disappearance has captivated the world following the smash-hit podcast series The Teacher's Pet.

READ MORE: Thirty-Six Years On, What Happened To Lyn Dawson?

READ MORE: Smash Hit Aussie Podcast 'The Teacher's Pet' To End -- For Now

Suspicions were raised about Chris Dawson's involvement when he moved the teenage Curtis into his home two days after Lyn went missing in 1982.

Lyn Dawson during the Chequerboard interview. Image: ABC/ The Teacher's Pet

The pair moved to Queensland soon after, where they married and had a daughter.

Chris Dawson has always maintained his innocence in is wife's disappearance.