Book excerpt: Dealing with some of the most heinous crimes imaginable, forensic neuropsychologist and psychoanalyst Dr. Richard Lettieri gives a behind-the-scenes look at criminal psychology through case studies from his over 30 years of experience as a court-appointed and privately retained psychologist. With cases like Michael, who stabbed his mother in the back believing she was the evil force causing the sun to descend upon the earth and gobble him up, and Tina, who seriously injured her boyfriend and stabbed his son to death, Decoding Madness is filled with gripping stories and forensic analysis. Through psychological examination, it is the author’s job to conclude whether these individuals are truly guilty and understand their actions are wrong, or if these individuals are not guilty by reason of insanity and instead require treatment. Decoding Madness offers a nuanced psychological understanding of defendants and their personal complexities beyond the usual clinical accounts. The book introduces the novel idea of the daimonic as a basic force of human nature that is the source of our constructive and destructive capacities and argues for an update to the criminal justice system’s perspective on rationality and conscious thinking. Featuring new findings and personal insights, Dr. Lettieri presents an engrossing view of the psychology of defendants accused of committing heinous crimes and the insight that they provide towards the human mind.