The then-teenager babysitter who was "installed" into Chris Dawson's home following the disappearance of his wife has denied he was "mucking around" when he pulled off her G-string, an Australian court has heard. 

Former rugby league player Dawson, 73, is standing trial and has pleaded not guilty to the murder of his wife Lynette Dawson who disappeared from their Bayview home in January 1982. 

The woman – who can only be known as JC – had told the court she was Dawson's student at a school where he taught. 

She later became the couple's live-in babysitter in late 1981, during which time she would have sex with him while his wife was asleep, she said during three days of evidence which concluded on Monday morning. 

The woman, who can only be known as JC, has given evidence during Chris Dawson's murder trial. Photo / NCA NewsWire 

Following Lynette's disappearance on January 9, 1982, JC says she was moved into Dawson's home on Sydney's north shore to help look after his two young children. 

She went on to marry Dawson in 1984 before later divorcing in acrimonious circumstances in 1990. 

She has told the court that during her marriage she was the victim of domestic violence including one incident in which he ripped off a G-string she was "parading" for him. 

JC previously told the court Dawson had become angry when he told her to only wear the underwear in front of him, describing the incident as "frightening". 

Under cross examination from Dawson's barrister, Pauline David, on Monday morning, JC denied the incident was nonviolent. 

"There was an incident with a G-string that involved Dawson pulling it from the back in the context of you mucking around," David said. 

"No," JC replied. 

"There was no violence associated with any G-string incident," David said. 

"There was, I was there," JC said. 

A picture of JC from 1981 on the day she and Chris Dawson left to start a new life in Queensland. Photo / Supplied 

JC and Dawson attempted to run off to Queensland to start a new life shortly before Christmas in 1981, only to turn around when she became ill and asked that he drive her back to Sydney. 

In early 1982, she travelled to South West Rocks to holiday with friends and family, however she says she kept in daily phone contact with Dawson. 

She said during one call he told her "Lyn's gone, she's not coming back" before he drove up to the NSW Mid North Coast to collect her to take her back to Sydney's north shore. 

JC has told the court she was driven back to Sydney on or about January 10, 11 or 12. 

Dawson disappeared on January 9, after she was dropped off at a Mona Vale bus stop by Dawson. 

David questioned whether JC had initially moved back in with her mother before she went to live at Dawson's home at Gilwinga Drive. 

"I want to suggest part of that process was moving back into your mother's place … And that there was some discussion before that actually occurred," David said. 

"There was not," JC said. 

"He came up to get me to install me into his place to look after his children and take care of the cooking and cleaning et cetera because he told me his wife was not coming back." 

The trial continues. 

- by Steve Zemek, news.com.au