CLEVELAND -- He was well-liked by neighbors, worked as a school bus driver and was a respected local musician who even appeared on Fox 8 News years ago.
So how did Ariel Castro keep such a horrific, dark secret for more than a decade? How did he lead a double life?
"We all have our internal masks and external masks," explained Criminologist Dr. David Licate on Friday's Fox 8 News in the Morning. "This type of individual is going to be able to conceal their motive."
He allegedly held them for 10 years, but never killed them. Did Castro look at Amanda Berry, Gina DeJesus and Michelle Knight as family? Or was it just about control?
"His psychological gratification may have been dominance," Licate said. "Maintaining and controlling -- that's where he was being fulfilled."
Was Castro born with these personality traits, or did he adopt them later on in life?
"There's no one factor that you can identify that you can explain violent behavior or sexual coercion. It's the nature or nurture debate: Was he born (with it)? Is it genetic? Was there brain trauma? Or was he socialized in some way? Was he abused? Was there a life course event that occurred that was that breaking point?" Licate said.
With kidnapping and rape charges looming, questions arise about how Castro will plead: is he a candidate for the insanity plea?
Not necessarily, according to Licate.
"I would argue that his behavior was very rational and calculated."
And while he's not a psychologist, Licate pondered how someone could pull off such an egregious crime for so long.
"Just the ability to carry this off for 10 years shows a high level of functioning. If you have a mental disease, you'll have a low level of functioning."
Castro remains under suicide precaution at the Cuyahoga County Jail, where he's being held on $8 million cash bond.