Soledad O'Brien reports on criminally insane felons and why the warning signs in individuals are sometimes missed. Included are interviews with Lionel Dahmer, serial killer Jeffrey Dahmer's father; and David Kaczynski, brother of the Unabomber, Ted Kaczynski.
click here to see where to watch or .
Ready to Watch CNN Special Investigations Unit, Season 2007, Episode 15?