- TOP STORY: Drew Peterson guilty of first-degree murder
- PHOTOS: Drew Peterson Murder Trial Timeline
- PHOTOS: Key Players in Drew Peterson Murder Trial
- VIDEO: Watch as verdict announced on ABC7
- VIDEO: Savio family talks to media after guilty verdict
- VIDEO: Stacy's sister talks to media after Peterson guilty verdict
- VIDEO: Drew Peterson's defense attorneys promise appeal
- VIDEO: Peterson prosecutor James Glasgow talks to media
- VIDEO: Pam Bosco, Stacy Peterson family spokesperson, reacts
In this Intelligence Report: the next move against Peterson will involve likely murder charges in the disappearance of his fourth wife, Stacy Peterson.
The disappearance of Stacy Peterson is the "one" yet to go for Will County authorities and for the woman's friends and family.
Even with Drew Peterson behind bars, the pressure is not off prosecutors, who are already looking toward a second round of grand jury presentations aimed at justice for Stacy Peterson.
"This man has to pay for Stacy," said Stacy Peterson family rep Pamela Bosco. "There is no reason why he shouldn't be brought back into court and face another jury and be put through the same hell he faced the last five weeks."
The family and friends of Stacy Peterson are not willing to rest on just one murder conviction. And neither are Will County prosecutors.
It was the unexplainable disappearance of Drew Peterson's fourth and most recent wife Stacy in 2007 that led to suspicions about the death of wife number three, Kathleen Savio, and the exhumation of her body.
When a forensic pathologist determined Savio's remains suggested homicide, Drew Peterson ended up charged -- and now convicted -- based partly on hearsay evidence from things said by Stacy herself before she "disappeared."
"She knew how he killed Kathy," Bosco said. "One way or another, he was not going to silence her and he didn't. He thought he would, but he couldn't, she was heard loud and clear to that jury and they weren't going to let him get away with it."
It will be five years next month that Stacy Peterson was last seen alive. Without a body, authorities admit it would be difficult to prosecute Peterson, but not impossible.
First, prosecutors would have to prove Stacy is no longer alive, then that a murder occurred, much in the same way they convinced jurors that Kathleen Savio's bathtub death was no accident.
"The longer someone is gone, the easier it is to prove they haven't just run away and that they are deceased," said Will County State's Attorney James Glasgow. "October 28, 2007, is in our rearview mirror now. We are going to look at that cases and assess it, and if we feel confident in going forward, we will be doing so."
"If they bring a case based on Stacy, based on this case, and then this case is overturned that would be a flawed prosecution so, the prosecution may want to think that through," said Drew Peterson's attorney Joel Brodsky.
In law there is a Latin term corpus delecti -- the body of the crime -- taken to mean that a body is necessary to serve as evidence of murder. But there have been dozens of cases in the U.S. where people have been convicted of murder even though no corpse was ever found. on only a very few occasions has the supposed "victim" later turned up alive.