The first witness to testify in the trial was the woman who found Savio dead in her bathtub in 2004.
Mary Pontrelli, a close friend and neighbor of Savio's, said that she knew Savio and Peterson had a rocky marriage that exploded when Savio discovered Peterson was cheating on her with another woman.
"She did find out he was cheating on her and she was very upset by that," Pontrelli said. "She did change the locks on the front door."
Savio also had a deadbolt installed on her bedroom door, a door which had a large hole in it when photographed by investigators after Savio's death, direct questioning of Pontrelli revealed.
Pontrelli described the Monday night when Drew Peterson came to her home and said he had not been able to reach Savio for 24 hours. He was trying to drop his children off at Savio's house after a weekend in his custody.
According to Pontrelli's testimony, Peterson and Pontrelli first contacted Savio's boyfriend and then a locksmith to get into SAvio's home to check on her. Once inside, Peterson waited downstairs and checked the garage for Savio's car while Pontrelli went upstairs and found Savio dead in her bathtub, her hair soaked in blood.
Peterson then came upstairs and took Savio's pulse, Pontrelli said. At some point in the night, Peterson told Pontrelli he was the beneficiary of Savio's will, Pontrelli said.
Defense attorneys, upon cross-examination, pointed out the Pontrelli had changed the details of her story in various accounts she gave to police, prosecutors, and grand juries. Pontrelli said she could not remember what she told police the night of the incident.