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Nearly five years since the disappearance of his fourth wife, former Illinois police officer Drew Peterson will be tried for the murder of his third wife in a high-profile case that gets under way Tuesday.

An Illinois court will hear opening arguments Tuesday in the case against Peterson, 58, who is charged with the 2004 death of his third wife, Kathleen Savio. Her death was ruled accidental until police began investigating the 2007 disappearance of his fourth wife, Stacy Peterson.

Stacy Peterson's body has never been found, but authorities believe she is dead and have named the former suburban Chicago police officer a suspect. Peterson, meanwhile, contends that the 23-year-old mother of two ran off with another man -- a claim Stacy Peterson's family vehemently disputes.

Savio's body was found in a dry bathtub in her home, her hair soaked in blood, just before her divorce settlement with Peterson was to be finalized in 2004. Peterson allegedly feared the settlement with the 40-year-old Savio would wipe him out financially. He has pleaded not guilty in her death.

A jury in the murder case against Peterson was selected last week. The panel of seven men and five women includes a part-time poet, a U.S. letter carrier, a woman who likes to read the National Enquirer and a research technician whose favorite TV show is "Criminal Minds." The jury also includes three male alternates and one female alternate. Nine jurors are white, two are African-Americans and one is Hispanic.

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Opening statements will begin Tuesday, and prosecutors are expected to call their first witnesses later that same day.

While Peterson is a defendant in the Savio case, Stacy Peterson's family is convinced of his guilt and confident they will see him tried for her murder.

"He has not been charged because we don’t have a body," Stacy Peterson's aunt, Candace Aikin, told FoxNews.com last week. "But I believe that things are progressing with the investigation in a good way."

The bitterness between Peterson and his former wives' relatives has often played out in the media.

When Peterson appeared on a talk show on Chicago's WLS-AM radio in 2009 to declare his innocence, Stacy's younger sister, Cassandra Cales, called in to confront him. Cursing, she told him, "You murdered my sister. ... You will pay."

After his arrest months later, Cales delighted in seeing him shackled at his arraignment. "It made me feel good to see him chained up like the dog that he is," she told reporters.

Peterson has tried to paint Stacy Peterson's family as dysfunctional. He has alluded to the checkered background of Stacy's brother, who spent time in prison for a sex offense. He also has mentioned how Stacy's biological mother, Christie Cales, disappeared in 1998.

Joel Brodsky, Drew Peterson's lawyer, said that is relevant to Stacy's disappearance.

"In her world, mothers run off and leave," he said. "To you, it is not an acceptable behavior, but in her world it is. Her mother did it."

Cales said she and her sister always believed their mother was killed, not that she abandoned them.

As far as Savio's family, her father and sister filed a wrongful death lawsuit in 2009, alleging Peterson went to Savio's house on Feb. 28, 2004, to "brutally ... stalk, attack, repeatedly beat, then drown (her)." Savio's body was found slumped forward in a dry bathtub, her hair soaked in blood. Savio's death was initially ruled accidental, but her body was exhumed following Stacy's disappearance in 2007.

Peterson shot back in comments to the Chicago Sun-Times, saying about the Savios, "They're up to their money-grubbing tricks again."

Last year, one of Savio's brothers wrote an open letter complaining that too much attention was directed at Peterson, rather than to Savio.

"I want to hear something about my sister that does not involve, include or revolve around Drew Peterson or his family," Henry Savio wrote.

"People that knew her loved her," he continued. "People that did not know her, noticed her."

Fox News' Marla Cichowski, Cristina Corbin and the Associated Press contributed to this report.