Robert Ian Trebeck.
Robert Ian Trebeck. Photo Facebook

DNA '100 billion times' likely from accused killer: court

DNA found on Alexis Jeffery taken where her body was found on the banks of the Macintyre River in 2014 was "100 billion times more likely” to be from her accused killer, a court heard.

Swabs taken from Ms Jeffery's body were tested against a number of samples taken by police during the investigation into her murder, the Toowoomba Supreme Court heard.

Queensland Health DNA analysis unit scientist Matthew Hunt told the court swabs taken from Ms Jeffery's jaw and breast were "100 billion times more likely” to be from Robert Ian Trebeck.

Trebeck has pleaded not guilty to Ms Jeffery's murder after she was found on the banks of the river the morning of March 16, 2014.

Samples taken from other parts of the young mother's body, including her stomach, right shoulder, both thighs, left foot, rib area and left shoulder, he said, also matched although to lesser quantifiable degrees.

Goondiwindi woman Alexis Jeffery. Photo from Facebook.

Photo Contributed
Goondiwindi woman Alexis Jeffery.

Traces from two other men were also found from samples collected at the scene.

DNA belonging to Daniel Rowsell, who Trebeck's legal team has suggested was responsible for Ms Jeffery's death, was not found, Mr Hunt said.

Police forensic scientific officer Senior Constable Mandy Watene earlier told the court she initially examined the crime scene from a boat due to the location where Ms Jeffery had been found.

Responsible for collecting samples from evidence seized by police, Snr Const Watene said no blood had been found inside cars belonging to Mr Rowsell and Trebeck, or on their clothing.

The trial before Justice Glenn Martin AM resumes on Monday morning.