Commonalities in Missing America 411 North America and Beyond

David Perry: In 99% of the cases, or more, maybe 99.5%, there's never even a suspect named in the case. The vetting factor that we use before we'll even include a case in any of the books and studies is mental health. If there's any evidence of animal predation, you know, animal attack, killing, dragging away, anything like that, we won't use the case. So what we're left with is a series of who done it. We've found some other commonalities that you have listed in the Missing 411 series.