Vic woman shot five times 'already dead'

The body of a 33-year-old mother was in three pieces when it was recovered from a mineshaft, a Melbourne murder trial has been told.

Forensic pathologist Linda Isles said Simone Quinlan's head, pelvis and torso were discovered in a mine shaft near Bendigo in 2015 and her remains had been burnt and covered with tape.

Wayne Marmo is on trial in the Victorian Supreme Court for Ms Quinlan's murder, having shot her in the head five times and dumped her body in a mineshaft near Bendigo. He also used petrol to set her body on fire on August 25, 2015.

However, his defence says Ms Quinlan was already dead when Marmo shot her, making him guilty instead of the lesser crime of attempted murder.

He said the person responsible was her violent boyfriend, Brendan Neil.

Pathologists have been unable to determine the exact cause of Ms Quinlan's death.

Dr Isles found there were three potential causes - gunshot wounds to the head, blunt impact to the head, or the blocking of Ms Quinlan's airways as a result of having her nose and mouth taped up.

She was unable to say when the gunshot wounds occurred, but determined they were fatal and likely occurred after Ms Quinlan received blunt force trauma injuries.

The court has heard from a witness, identified as TS, that Neil beat and kicked Ms Quinlan in a prolonged and bloody attack during an "ice rage".

TS told the court Ms Quinlan "looked lifeless through most of" the attack, making a few sounds during the beating.

Meanwhile, she and two others smoked ice at the kitchen table.

TS also told the court that during the beating, Marmo began filing the barrel off a shotgun.

After the beating, she alleged Ms Quinlan was wrapped in a blanket and placed in the ute tray of Marmo's Hilux.

She said she overheard Marmo tell Neil he had to "get rid of her" because "she's snitched before".

TS said she accompanied Marmo on a drive to find a mineshaft into which he and another friend dumped Ms Quinlan's body.

She said on the way, Marmo pulled over and shot Ms Quinlan "maybe five" times to ensure she was dead and "put her out of her misery".

She was then dumped down a mine shaft and set alight.

The trial continues next week.