a severe mental disorder characterized by some, but not necessarily all, of the following features: emotional blunting, intellectual deterioration, social isolation, disorganized speech and behavior, delusions, and hallucinations.
the predominant or prevailing tendency of one's spirits; natural mental and emotional outlook or mood; characteristic attitude
1. 'He was nuts, but he was a small-town boy. He was afraid to go to big places, afraid of the people he might meet. And he didn't seem to be smart enough, or to have the will, to ignore those fears.' (pg 354)
This shows imagery; in this passage Lucas is describing their murderer. Since they have now found who their killer is they need to get background information and pictures, any kind of information they have on Charlie Pope. This helps describe the personality of this murderer.
The emerging theme in this book is still the same as before. Lucas and Sloan are trying to solve two murders that were identical. So far the only part that has changed is that they now have their killer. They're trying to find Charlie Pope; as they're searching they've discovered some new information about Charlie from his old inmates at the psych ward. They've been piecing together the story and have found out that Charlie could possibly just be a pawn in The Big Three's plan.