The public by and large is not fond of criminals who go free at the end, though they are more acceptable in books than in television and movie adaptations. Even though censorship has eased, a book is altogether more eligible for television and movie sales if the hero-criminal is caught, punished, and made to feel awful at the end. It is almost preferable to kill him in the course of the story, if the law is not going to. This goes against my grain, as I rather like criminals and find them endless interesting, unless they are monotonously and stupidly brutal.
Criminals are dramatically interesting, because for a time at least they are active, free in spirit, and they do not knuckle down to anyone. I am so law-abiding, I can tremble before a customs inspector with nothing contraband in my suitcases. Perhaps I have some severe and severely repressed criminal drive in myself, or I would not take such an interest in criminals or write about them so often. And I think many suspense writers—except perhaps those whose heroes and heroines are the wronged and victimized parties, and whose villains are off-scene, unattractive or doomed—must have some kind of sympathy and identification with criminals, or they would not become emotionally engrossed in books about them. The suspense book is vastly different from the mystery story in this respect. The suspense writer often deals much more closely with the criminal mind, because the criminal is usually known throughout the book, and the writer has to describe what is going on in his head. Unless a writer is sympathetic, he cannot do this.
I find the public passion for justice quite boring and artificial, for neither life nor nature cares if justice is ever done or not. The public wants to see the law triumph, or at least the general public does, though at the same time the public likes brutality. The brutality must be on the right side, however. Sleuth-heroes can be brutal, sexually unscrupulous, kickers of women, and still be popular heroes, because they are chasing something worse than themselves, presumably.
-from Plotting and Writing Suspense Fiction by Patricia Highsmith
