Chris Dawson’s former brother-in-law has told a court he believes the former rugby league player is guilty of murdering his wife Lynette in January 1982.

Greg Simms continued his evidence on Wednesday in the NSW Supreme Court trial of Dawson, 73, who has pleaded not guilty to the murder.

“You have taken the view, haven’t you, that Mr Dawson is guilty?” Dawson’s barrister Pauline David asked.

“I believe so, yes,” Mr Simms said.

Ms David suggested Mr Simms had painted her client in a unfair light because he was so desperate to get closure about Ms Dawson’s disappearance.

The Crown claims Mr Dawson murdered his wife – who disappeared from their Bayview home on Sydney’s northern beaches – and disposed of her body because of his affair with one of his students, known as JC.

Mr Dawson’s legal team has argued at the trial that he might have failed his wife as a husband, but he did not kill her.

Mr Simms said his attitude towards Mr Dawson and his beliefs about what had happened to his sister shifted after a discussion in early 1990 when JC said Mr Dawson had wanted to hire a hitman to get rid of his wife.

“What is your attitude to Mr Dawson today?” Ms David said.

“Well, I wouldn’t want to speak to him,” Mr Simms said.

Ms David questioned whether Mr Simms’ testimony had been altered because of his previous conversations with Rebecca Hazel, who wrote a book about Ms Dawson’s disappearance, and through what others had said in The Teacher’s Pet podcast on the topic.

Mr Simms’ wife Merilyn also took the stand on Wednesday, saying Ms Dawson was always anxious about using her bank card while shopping because it would make her husband angry.

“He didn’t like her using the bank card and spending the money because then he would have to pay the bills,” she told the court.

Ms Simms gave her version of the 1990 meeting with JC who is alleged to have said that Mr Dawson had taunted and teased his wife, and that he had given her alcoholic drinks at night so she would fall asleep while he had sex with JC.

Ms Simms said the last time she spoke to Ms Dawson was in October 1981. At the time, Ms Dawson was very upset, saying her husband was angry and evasive, and that their sexual relations had broken down.

Ms Dawson was also upset that her husband had wanted to move JC into their home so she could study her HSC, Ms Simms told the court.

She described a phone call from Mr Dawson in September 1982, almost 10 months after Ms Dawson’s disappearance, when his two children were visiting their family farm. At the time, Mr Dawson accused the Simms family of abducting the children and secretly taking them to see his wife.

“He was very angry and agitated, and he said that he wanted Lyn to come back, he wanted to see her walk in the door, and that he missed her,” Ms Simms said.

The judge-alone trial continues.

– AAP