Najma Carroll, 33, was killed on July 14, 2020 and her body discovered 15 days later by a bushwalker hiking through the Sandy Point area.
The 46-year-old unsuccessfully argued that a man he sold drugs with, Robert Sloan, was the one who beat Carroll and attempted to dispose of her corpse by dousing it in petrol and setting it alight.
An anthropologist who examined her badly burnt body discovered her cranium shattered into 62 fragments consistent with blunt force trauma, the court heard.
Parkes, Sloan and Carroll met each other while staying at the Hunts Hotel in Liverpool in Sydney’s southwest.
In February as the trial kicked off, crown prosecutor Darren Robinson told jurors that Carroll had “invested” $8000 in their illegal drugs business by drawing from her superannuation.
The jury heard Parkes was worried Carroll “knew too much” about his drug business and formed an agreement with Sloan to kill her.
Robinson told jurors the pair arranged to take her from the Hunts Hotel to an acquaintance’s house in Smithfield where she stayed in his garage before being killed.
Parkes denied his intention was murder, saying he arrived at the Sandy Point site with a jerry can of petrol to set fire to Carroll’s SUV out of concerns it could be linked to their drugs business.
He will face a sentence hearing on May 24.
