The Crown has alleged Gayle was brutally beaten by both parents, one wielding a bat, the other a barbecue tool. During the trial, both parents have accused the other of being responsible for the death of the teen, whose badly beaten body was found in a bathtub in her parents' Brampton home in June 2010.
Tiffany Gayle’s blood was found on the clothing of both parents, and their bloodied footprints were found in the basement.
The Crown alleges Tiffany’s killing was a team act, carried out by both parents.
During closing arguments, Elizabeth Gayle's lawyer Don McLeod argued that his client was so distraught after Tiffany's death that paramedics arriving at the scene had to check her vital signs, whereas Federick Gayle was calm and composed.
The Crown, however, has argued that even if Elizabeth Gayle was only a witness to the crime, she should still be held accountable for failing to stop it or call for help.
McLeod has argued his client may have found it difficult to call 911 during or after the killing because the perpetrator of the crime was right beside her after the beating occurred.