Riley Fox Case: Tracking Down Riley's Killer

June 10, 2010— -- The slaying of 3-year-old Riley Fox was a crime that rocked the small community of Wilmington, Illinois.

The little girl was kidnapped from the living room of her own home in 2004 and was found face down in a creek in the Forsythe Woods, about two miles from the Fox residence. Riley had been sexually assaulted, bound, gagged with duct tape and drowned.

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It was not until six years later -- after police incorrectly charged the young girl's father, Kevin Fox, with the murder -- that investigators tracked down the man now they now believe to be the real killer.

Scott Eby, a 38-year-old imprisoned sex offender, was charged on five counts of first-degree murder and one count of predatory sexual assault last month, after DNA evidence allegedly linked him to the crime. He is expected to plead not guilty to the long-unsolved murder.

At the time of Riley's murder, Eby was on parole and living about a mile away from the Fox home. Eby had no connection to the Fox family, but he had an extensive criminal history.

Eby was sent to prison for a separate 2005 charge of criminal sexual assault of a family member, according to the Illinois sex offender registry. He has been in and out of prison since 1988 on charges including forgery and a string of burglaries.

Tracking Down Riley's Killer

The FBI got involved in the investigation in 2009, just months after "20/20" first reported on the case. Agents came to the neighborhood, conducted interviews and came up with new leads, according to Will County State's Attorney James Glasgow.

One of those leads came from Eby's former girlfriend, who lived down the block from the Foxes at the time of Riley's murder. During the months that she dated Eby, the girlfriend, who asked that her identity not be revealed, described him as a "dishonest" "creep" with a dark past.

"His mom told me when he was like 15 that, he was mad at his dad, and he cut his dad's brake lines," she said. "So that was creepy to me, and awful, and ... it was one of [the] many things that creeped me out about him."

She said she also found other parts of Eby's behavior disturbing, including one episode at a hotel where they got in fight and she said she saw a noose hanging there. She thought he would threaten suicide, but said the noose was later taken down.

More important to investigators, she recalled sitting with Eby in a memorial garden dedicated to Riley Fox where they discussed the girl's death.

"I was saying, 'I can't believe somebody did that to that sweet little girl.' And he said, 'Oh, that was such a shame, wasn't it?' And the way he said was like cold, like he didn't mean it," she said. "It was like an actor reading a script that didn't know how to act. And for some reason it just stuck in my head."

Eby's insincere tone struck her as odd and when the FBI knocked on her door by chance last year, she opened up to investigators.

"It was just an inkling I had that when they came I was very grateful to get it off my chest and tell someone what I felt," she said.

Eby had no connection to the Fox family, and his girlfriend doesn't recall him ever mentioning Riley's murder again, but his extensive criminal past was enough to land him on the FBI's list of potential suspects. Eventually, they tracked him down in prison.

"Apparently, [the police] received a tip that led them to go to the prison where he is currently incarcerated," said Kathleen Zellner, the Fox family's attorney. "They spoke to him, they got a DNA sample, the state lab cooperated in quickly getting the test result. They returned to the prison within 24 hours and they were able to get a statement from him confessing to the crime."

Zellner said Eby made a full confession.

Missed Clues, Missed Opportunities

For Melissa and Kevin Fox, compounding their pain, is the conviction that there were so many missed clues and opportunities to catch the killer quickly.

According to Zellner, the day of Riley's disappearance, police responded to a reported suicide threat at Eby's house.

"Eby was so nervous when the police were in there. He was vomiting, leaving the room to vomit. And he also asked them if that -- and the exact quote is, 'Has that little girl been found yet?'" Zellner said. "You've got somebody trying to kill themselves, feeling remorse. And they're making an inquiry about this little girl."

Zellner said that police missed many red flags that they should have picked up on. "From the burglary convictions, to the subsequent sexual assault, to the suicide attempts, to the inquiries about Riley, I mean, he did everything but set a siren off at his house -- 'I'm the guy,'" she said.

Riley's mother Melissa Fox said police were so focused on Kevin Fox that that they did not stop to give Eby a real look. "They had blinders on so they didn't see any of that stuff," she said.

Kevin Fox spent eight months in prison before he was released and ultimately cleared through DNA evidence. The family sued the state and won $15 million, which was later reduced to $8.5 million.

Armed with what he called "substantial evidence" collected by the FBI, Glasgow is confident in his case against Eby and said he is assessing whether to seek the death penalty.

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