(CNN) -- The jury in the Drew Peterson murder trial deliberated for more than eight hours Wednesday before a judge sent them home for the night.
Peterson, a former Chicago-area police sergeant, is accused of killing his ex-wife, Kathleen Savio, in 2004.
The seven men and five women began deliberating Wednesday morning and asked during their discussions to hear again from the testimony of a defense witnesses, Harry Smith, who was Savio's divorce attorney, and a prosecution witness, Neil Schori, a pastor.
Schori had testified that Peterson's fourth wife, Stacy Peterson, told him she woke up alone the night Savio died and Drew Peterson later coached her on how to talk to police about his whereabouts that night.
Smith had testified that Stacy Peterson asked him, "She wanted to know if, in my opinion, the fact that he'd killed Kathy could be used against him."
After 8 1/2 of deliberations, Judge Edward Burmila sent the jury home for the night.
When Stacey Peterson went missing in October 2007, investigators said they would look again at Savio's death, which was initially ruled a drowning. Stacey Peterson still has not been found and Drew is considered a suspect in the case.
Savio was found dead in her dry, clean bathtub March 1, 2004.
Savio's death was ruled a homicide in February 2008, and Peterson was later arrested and indicted on first-degree murder.
On Wednesday, the jury also asked for Drew Peterson's and Stacy Peterson's phone records for the weekend Savio died.
"There's a lot for the jury to go through. This is an entirely circumstantial case," Beth Karas, a legal correspondent at In Session, which airs on CNN sister network TruTV, said.
Peterson was married to Savio in 2001 when he had an affair with then-17-year-old Stacy Cales, who became his fourth wife. Savio and Peterson filed for divorce in October 2001 and their relationship remained contentious for the next several years.
Bolingbrook police records indicate officers were called to Savio's home 18 times to intervene in domestic fights from 2002 to 2004. Peterson had Savio arrested twice for domestic violence, though she was found not guilty in both cases.
On February 27, 2004, Peterson picked up his two sons from Savio's home and spent the next two days with them. Prosecutors believe he entered her home again early on February 29 and killed her.
At the time of her death, which authorities initially treated as an accident, a court was mulling how the couple's marital assets would be divided, and Savio was set to receive part of Peterson's pension and other support.
In Session's Michael Christian and Graham Winch contributed to this report.