KUSA - As human beings, we always want to know why - especially when something terrible happens. Because if we know why, it might be possible to prevent it from happening again.
When it comes to Austin Sigg, a teenager who killed 10-year-old Jessica Ridgeway, answers are hard to find.
A well-known expert in sex-offender behavior, Dr. Anna Salter, studied Sigg and testified in court for the prosecution during Sigg's sentencing hearing.
"Fortunately, there aren't a lot of these cases," she said in an interview at her Madison, Wis. office.
It's Salter's job to interview, study and make sense out of people like Sigg, if that's possible.
"People can't make sense of offenders who do this kind of thing," Salter said. "They are so very rare and so very malevolent that often people just are befuddled, 'how could any human being do this kind of things?'"
She wasn't able to definitively come up with an answer after reviewing thousands of pages of evidence and hours of interviews with families and Sigg himself. In November 2013, the 18-year-old was sentenced to life in prison.
"He's a sexual sadist, but I also think he's a necrophiliac," Salter said.
The question is, what is obvious: could people around him see this coming?
"He was living a secret life," she said. "And that's all there was to it. No one knew what he was up to. He clearly came forward not out of the sense of guilt or regret, but because he was about to be caught. He talked as matter-of-factly about killing her as he would have about going to a grocery store. At one point he was eating a sandwich while describing dismembering her."
So, how did Sigg become Sigg?
"We don't have any easy answers on that. We don't have any answers period," Salter said.
Can we help him?
"Currently, we don't have any research to suggest we can fix someone like this," she suggested.
But asking questions and studying them may lead to answers eventually.
"What other hope is there, except to make enough sense of it to begin to develop some kind of way to prevent it," Salter said.
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