Men and Supermen: The Nietzsche Syndrome
Two elderly women were found murdered in their home. One was a pawnbroker, the other her unfortunate stepsister. The pawnbroker was killed with several blows to the back of the skull by a blunt weapon; the latter was hit on the top of her head with what appeared to have been an ax blade. No weapon was found at the scene, but the killer cleaned blood off himself there. Although some money and a few trivial items were taken, robbery did not appear to have been the motive.
The detective in charge of the case, Inspector Porfiry Petrovich, was faced with the task of interviewing every client who had done business with the pawnbroker, watching for clues from any of them that might point to their involvement. This is one of the earliest examples of criminal profiling to appear in fiction: Fyodor Dostoevsky wrote about the crime and the perpetrator in his classic 1866 novel, Crime and Punishment. He was responding to the intellectual idea that some people are above the social conventions of morality, grounded in the ideas about the hierarchy of masters and slaves proposed by philosopher Georg W. F. Hegel.
Petrovich interviewed all business associates and investigated their lives. He discovered that a student named Raskolnikov had recently been ill, had failed to pay his rent (so he needed money), and had published an article on the idea of the extraordinary man who can commit crimes without moral accountability. That made him a likely suspect. Petrovich realized that if Raskolnikov is the murderer, he would have to be approached with some cleverness. When Raskolnikov failed to yield to trickery, the Inspector subtly pressured him into believing that he was a primary suspect and under surveillance. It worked. Eventually, Raskolnikov broke down under the strain of guilt and paranoia, believing that he had killed his own humanity, and confessed.
The point of the novel was that people are bound by a conscience and an intellectual exercise about their superiority doesn't necessarily play out when put into practice. However, Raskolnikov was clearly not a psychopath. He was an immature student seeking philosophical justification for an act he did not even understand. In fact, among those teams of killers such as Leopold and Loeb, one is often psychopathic and thus resistant to guilt, while the other is quite similar to Raskolnikov: unstable, arrogant, and inevitably unable to sustain the idea of his moral superiority. The next case is a perfect example.