Here's a guide to some key questions in the case of Drew Peterson, on trial for first-degree murder in the 2004 death of his third wife, Kathleen Savio:
Q: Who is Drew Peterson?
A: Drew Peterson, 58, is the brash, mustachioed former police sergeant from Bolingbrook, where he served for nearly three decades. He found tabloid fame with his over-the-top personality after the October 2007 disappearance of his fourth wife, Stacy Peterson. In November 2007 authorities exhumed the body of Peterson's third wife, 40-year-old Kathleen Savio, who was found dead in 2004 in a bathtub. By May 2009, Peterson was arrested and indicted in her murder. He has been jailed since, but his real-life drama continues to attract media attention and inspired a cable TV movie starring Rob Lowe.
Q: What happened to his wives?
A: Stacy Peterson was 17 when she started dating Drew Peterson, then 47. The couple married in October 2003. Four years later, Stacy Peterson went missing at age 23, last seen leaving home to visit a family member. She hasn't been heard from since. The couple had two young children at the time of her disappearance. Peterson and third wife Kathleen Savio were in the midst of a divorce when her death was ruled an accidental drowning in March 2004. Her body was exhumed and an autopsy was conducted less than a month after Stacy Peterson went missing. Will County prosecutors officially declared Savio's death a homicide in February 2008.
Q: What is hearsay evidence? Why are prosecutors being allowed to present it?
A: Hearsay, or statements not based on the direct knowledge of a witness, usually isn't admissible in court. But Illinois judges can allow it in murder trials if prosecutors prove a defendant may have killed a witness to prevent him or her from testifying. Peterson's case went through several appeals before a state appellate court ruled in April that prosecutors could present certain secondhand statements. That ruling gave the go-ahead for Peterson's trial and was considered a victory for the Will County state's attorney. Peterson's defense attorneys chose not to appeal to the Illinois Supreme Court, instead saying they would let prosecutors try to prove their case.