A martial arts expert was motivated by “jealousy and possessiveness” when he murdered his girlfriend of about eight weeks and dumped her body in bushland, a court has been told.

Prosecutor Lee Carr SC told the NSW Supreme Court on Monday Sayle Newson inflicted a “significant degree of violence” on mother-of-two Carly McBride who weighed only 50 kilograms when she was brutally murdered.

Mr Carr said Ms McBride, 31, suffered 23 fractures to the head and another 13 to her ribs and back when attacked by the Muay Thai fighter who later boasted to police how he had won 20 out of 20 professional fights and been trained by world champions.

The prosecutor said Newson’s decision to dump Ms McBride’s body in Upper Hunter bushland had shown no respect for the woman he claimed to love.

“She was discarded as something of no worth and left to the elements and the scavenging of animals,” Mr Carr said during a sentencing hearing for Newson.

The prosecutor said he was unable to give a time frame as to how long Ms McBride had endured the attack by Newson who was angry and motivated by jealousy and possessiveness.

Ms McBride’s mother, Lorraine Williams, told the court in her victim impact statement her daughter had been her best friend and they had talked every day before she disappeared.

“She had goals and dreams and they were cruelly taken away from her,” Ms Williams said.

A Supreme Court jury sitting in Newcastle in June found Newson, 43, guilty of murdering Ms McBride on September 30, 2014, at Muswellbrook or elsewhere.

Justice Mark Ierace, sitting in Sydney on Monday because of COVID-19 restrictions, said he would sentence Newson at a later date.

The circumstantial case against Newson, of Buff Point on the Central Coast, was that he had the motive, opportunity and the martial arts skills to cause the multiple fractures suffered by Ms McBride.

Mr Carr had told the jury during a retrial after the first trial had to be aborted that Newson became aggressive and violent when drug affected and he had been taking ice for a couple of days before he killed Ms McBride.

Newson, who maintains his innocence and is planning to appeal his conviction, claimed Ms McBride could have been robbed and killed by a stranger or her ex-partner might have been involved.

Ms McBride’s remains were found in bushland at Owens Gap, about 17 kilometres northwest of Scone, on August 7, 2016. There had been no attempt to bury or conceal the body.

Ms McBride had met Newson at a drug and alcohol rehabilitation centre west of Wyong in late 2013 before they began a relationship in August 2014.

Newson had dropped off Ms McBride at her ex-partner’s Muswellbrook home at 12.30pm on the day she disappeared before he later intercepted her as she was walking to meet him at the local McDonald’s.

Newson murdered Ms McBride some time after 2pm before dumping her body.

The couple had argued two days earlier about Ms McBride communicating with other men on Facebook.

Police later found a map at Newson’s home where circles had been marked around Scone and Muswellbrook as well as the locations of point to point cameras between the two towns. The location where Ms McBride’s remains were found was inside one of the circled areas.

Newson sent a Facebook message to another woman at 5.30am the day after the murder asking if she wanted sex. The pair met up the following day and had sex.

AAP

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