micheal john duffy , 34 , pleaded not guilty to murdering colleen deborah ayers , 33 , whose decomposed body was uncovered in a shallow grave on her parent 's 25-acre lakesland property , located near picton , south west of sydney .
in the opening statements of duffy 's trial crown prosecutor elizabeth wilkins sc told the jury , that while his former flame had a ` twisted desire to kill ' and that he had initiated the violent act , duffy had willingly joined in .
he claimed his co-accused , evans , was the one who had a ` twisted desire to kill ' and he had only disposed of her body .