Kerrie at Mysteries in Paradise recently posted S. S. Van Dines Twenty Rules for Writing Detective Stories.
The post reminded me that I have been collecting rules and essays on writing detective/mystery/crime fiction for a while and thought I would contribute these links:
Monsignor Ronald A. Knox (1888-1957) was a British clergyman who also wrote detective fiction. He included Father Knox's Decalogue: the Ten Rules (of Golden Age) Detective Fiction in Best Detective Stories of 1928-29. The author of the web site thinks he was mostly joking and they are amusing now.
1. The criminal must be someone mentioned in the early part of the story, but must not be anyone whose thoughts the reader has been allowed to follow.
2. All supernatural or preternatural agencies are ruled out as a matter of course.
3. Not more than one secret room or passage is allowable.
4. No hitherto undiscovered poisons may be used, nor any appliance which will need a long scientific explanation at the end.
5. No Chinaman must figure in the story.
6. No accident must ever help the detective, nor must he ever have an unaccountable intuition which proves to be right.
7. The detective must not himself commit the crime.
8. The detective must not light on any clues which are not instantly produced for the inspection of the reader.
9. The stupid friend of the detective, the Watson, must not conceal any thoughts which pass through his mind; his intelligence must be slightly, but very slightly, below that of the average reader.
10. Twin brothers, and doubles generally, must not appear unless we have been duly prepared for them.
A serious list of rules is Raymond Chandler's Ten Commandments for the Detective Novel. I think they hold up well. The rules of Van Dine and Chandler overlap in several places.
1. It must be credibly motivated, both as to the original situation and the dénouement.
2. It must be technically sound as to the methods of murder and detection.
3. It must be realistic in character, setting and atmosphere. It must be about real people in a real world.
4. It must have a sound story value apart from the mystery element: i.e., the investigation itself must be an adventure worth reading.
5. It must have enough essential simplicity to be explained easily when the time comes.
6. It must baffle a reasonably intelligent reader.
7. The solution must seem inevitable once revealed.
8. It must not try to do everything at once. If it is a puzzle story operating in a rather cool, reasonable atmosphere, it cannot also be a violent adventure or a passionate romance.
9. It must punish the criminal in one way or another, not necessarily by operation of the law....If the detective fails to resolve the consequences of the crime, the story is an unresolved chord and leaves irritation behind it.
10.It must be honest with the reader.
Chandler also wrote The Simple Art of Murder, a still interesting essay on writing detective fiction. In it Chandler refers to A. A. Milne's one mystery, The Red House Mystery which I discussed on my old blog. I provide a link to Milne's introduction where he discusses his criteria for mysteries.
I enjoy investigating the antecedents to our modern crime stories.