A well-known follower of Freud here puts theory of psychoanalysis to bear on problems of crime, showing the importance of psychoanalysis as a detector. He illustrates his thesis first by taking clues, tracing (one must confess a bit vaguely) the link between deductive reasoning and psychological evidence, such as self betrayal, return to the scene of the crime, etc. He shows also a direct rooting back to primitive beliefs, black magic, superstition, and so on, then step by step, the transition to scientific processes. The part of his text deals with judicial errors, and the psychopathology of false judgment Throughout the book, he illustrates with factual evidence from true crime, and with cases. The text is translated from the German -- is heavy going -- and though a new angle, not one for the mystery fan.