Building a Case Against Drew Peterson

As Drew Peterson sits in jail on murder charges for his third wife's death, his stepbrother could prove key to the prosecution's case that he also killed his still-missing fourth wife, Stacy Peterson.

Drew Peterson is being held now only for the 2004 murder of Kathleen Savio, whose death the medical examiner had initially ruled a drowning accident. But a grand jury is still hearing evidence that alleges Peterson's involvement in Stacy Peterson's death.

Included in that evidence are statements from Thomas Morphey that he helped his stepbrother move a large blue barrel from Peterson's home on the last day Stacy Peterson was seen alive.

The day before he helped move the barrel, Morphey said Peterson confronted him. "He said, 'How much do you love me?'" Morphey told "Good Morning America" in March. "I said, 'I do.' And he said, 'Enough to kill for me?'"

Neither Stacy Peterson nor her body have ever been found, nor has the mysterious blue barrel.

While the allegations against Peterson and his seemingly blase attitude toward the fate of his two wives have made him an unpopular media figure, prosecutors face the burden of convincing a jury he's guilty using evidence that's reportedly circumstantial at this point.

Prosectors are hoping they can enter into evidence writings from Savio when she was in the midst of her divorce from Peterson, that she feared her husband's "next step is to take my children away or kill me."

Prosecutors are banking on a new Illinois state law that would essentially allow Savio's words to be heard from the grave. But the law allows such statements only if the witness was killed to prevent him or her from testifying.

"These statements are not subject to cross examination," legal analyst Dana Cole told "Good Morning America," "and under current U.S. Supreme Court rulings if a statement is not subject to cross examination it's hearsay and may be inadmissible."

Peterson's lawyer, Joel Brodsky, has said he'll challenge the law as unconstitutional.

Brodsky has called the $20 million bond "excessive" and said he hoped to get it reduced. Another attorney told The Associated Press that Peterson had an alibi for Savio's death.

The defense also plans to play up the results of Savio's first autopsy that ruled her death in the bathtub an accidental drowning. The second autopsy, done after Stacy Peterson disappeared in 2007, ruled Savio's death a homicide.

If a murder indictment is handed down in Stacy Peterson's death, experts said it could vastly change the case against Drew Peterson.

"Then I think the prosecution will combine both cases, and each case will sort of feed off the other and will present a powerful picture to both a trial judge and a jury that this guy is a serial murderer," Cole said.

Another Day in Court, More Jokes from Peterson

Despite the prosection's effort to portray him as a cold, calculating killer, Peterson maintained an eye-brow raising sense of humor as he was led into court last week.

Asked if he was looking forward to his day in court, Peterson, handcuffed and wearing a red jumpsuit, joked with reporters, saying, "What about this bling? Look at this bling. Three squares a day in this spiffy outfit. How can you beat that? Look at this bling. My God."

Even when he was first arrested Thursday, he joked, "I guess I should have returned those library books."

"He's an idiot," Susan Doman, Savio's sister, said today on "Good Morning America," dismayed that Peterson would make jokes after he was arrested for his wife's murder.

A judge postponed Peterson's arraignment until May 18 because neither of Peterson's attorneys were in court today, The Associated Press reported. Peterson didn't speak in court except to tell the judge he understood the continuance. He's being held on $20 million bond.

The indictment's legal language accuses Peterson of drowning Savio, saying that he forced her to "inhale fluid" and that he did it "with the intent to kill Kathleen Savio."

Savio's sister, Susan Doman, said the world is finally a "safe place for me" now that Peterson has been arrested.

Stacy Peterson's friends and family said last week that her husband's arrest is bittersweet.

"It's a very hollow victory right now not knowing where Stacy is," said Sharon Bychowski, a friend of Stacy Peterson who lives next door to Drew Peterson. "We still have a ways to go. It wasn't quite the victory I thought it would be."

Pam Bosco, a friend and family spokesman, said the family "understands that it's ongoing and we just have to be patient with it."

Lawyer: Peterson Takes Charges Seriously

Peterson has maintained his innocence to anyone who would listen both in Savio's death and Stacy Peterson's disappearance. At times he's even seemed to revel in the spotlight.

"Drew takes these charges very seriously," his lawyer Joel Brodsky told "Good Morning America." Those jokes, he said, are his way of dealing with stress. "That's just his nature."

Doman said the family hopes the arrest is the first step in justice for her sister. Peterson was arrested shortly before he was scheduled to fly to Reno to interview for a security job at a brothel featured on a cable television show.

"It was a big relief because he wasn't going on all these shows, going around joking and laughing," Doman said.

Andrew Abood, an attorney for Peterson, told The Associated Press the indictment was not a surprise because "there was tremendous pressure for the government to do something in this case."

He added Peterson had a "lock-tight alibi" because Peterson and Savio's teenage son said last month in a television interview that he was with his father at the time of his mother's death.

"I highly do not believe that my dad had murdered my mom," Thomas Peterson, 16, told CBS' "The Early Show." "Because, first off, he wasn't there. He was with us during that period of time."

Peterson, a former duty sergeant for the Bolingbrook Police Department, was the first officer to respond to the scene of Savio's death. His nearly-three-decade career in law enforcement ended when he stepped down after Stacy Peterson disappeared.

Brodsky said he had not spoken with his client as of late Thursday night, but expected to speak with him Friday.

The Associated Press contributed to this story.