The 20 Rules

As a reader and writer of mystery stories for most of my life, I have long ago learned about the basic rules of the genre. Every now and then, however, I stumble over a piece of information I find highly useful. Like “Twenty Rules for Writing Detective Stories” by. S.S. van Dine.

I stumbled upon this essay by S.S. van Dine while browsing one of my favourite sites for free e-books, Feedbooks (click here to find the e-book). I downloaded it and read it, realizing that part of the rules still are correct while others have changed over time. Let’s have a look at the twenty rules and see how they are today, shall we?

1. The reader must have equal opportunity to solve the crime. That one still is absolutely right. All clues must be visible and all information the detective gets must also be available for the reader.

2. No tricks or deceptions might be played on the reader safe for those also played on the detective by the criminal. That’s very much the same as ‘equal opportunity’ in my books, but it’s right, of course.

3. There must be no love interest in the story. Boy, that one flew right out of the window later, didn’t it? Van Dine argues that a mystery story is a venture for the mind and not for emotions, but I have to admit that a little bit of relationship stuff in a mystery story can surely spice things up.

4. The detective himself or one of the official investigators should never turn out to be the culprit. That one is a ‘yes, but’ case for me. Yes, the detective who is the main character of the story should never turn out to be the culprit. I have, however, read some mystery stories in which one of the official investigators turned out to be the culprit and they worked quite nicely.

5. The culprit must be found by logical deduction, not by accident, coincidence or an unmotivated confession. That one is definitely true. A good mystery story should never rely on accident or coincidence for the solution, it all has to be ‘there’ to be seen.

6. The detective novel must have a detective in it (read: a person who detects and searches for clues and logically interprets them). That basically goes without saying, as it were.

7. There must be a corpse in the story, the deader the better. Another of those ‘yes, but’ cases in my opinion. You can start a crime story with something less than a murder, but sooner or later the murder should come. It’s the most interesting crime to most readers and they expect at least one in a crime or mystery story.

8. The crime must be solved by naturalistic (read: scientific) means. This one is definitely right, but a patina of supernatural sometimes goes well with the story. Old-fashioned deduction can go a long way, even with all the help of a modern CSI unit.

9. There must be but one detective. I’ve seen stories with various detectives (adding up to ‘one’ detective) done very well, but there should be, in essence, one detective entity pitted against the reader.

10. The culprit must turn out to be a person who has played a more or less prominent role in the story. This one is absolutely right. There’s nothing worse than a story in which the culprit jumps out of the shadows at the end and has never been seen before. It falls under the rule of ‘equal opportunity’, by the way – for the reader has to meet all important characters and the culprit definitely is important.

11. Servants should never turn out to be the culprit. Another rule the change of times has done away with. Servants are rare today, outside the houses of the very rich (and usually very famous). As they’re not that common today, there’s no real reason to exclude them from the list of possible culprits.

12. There must be only one culprit. I don’t completely agree with this rule. It should be obvious, though, in some way after a while that there have to be two criminals around. I have read stories that work very well with two or more criminals.

13. Secret societies or criminal syndicates have no place in a detective story. I partly agree here. The culprit should not have a syndicate behind him and secret societies are fit better for a thriller or adventure story. There’s no reason, though, why one should not play a very minor role.

14. The method of murder must be scientific and logical (so it can be detected). Van Dine meant by this that there should be no ominous poison never seen or heard of before. He’s right about it, because otherwise there’s no way the reader can solve the crime.

15. The truth must be visible at all times, provided the reader is clever enough to see it. Clues must point at the right person, if you really think about them. The means of committing the murder must be there, visible to the detective and the reader. That’s absolutely right, of course.

16. A detective story should not contain long descriptive passages. I don’t really agree with van Dine here. I like to slip into the setting, so descriptions of the surroundings and the people are of essence to me. But that one might be off today mostly because we’ve grown more used to psychological solving of crimes than at van Dine’s time. Today, we need worked out characters, so we can see who has the motif on top of the means and also has the right characteristics to kill.

17. The culprit should never be a professional criminal. Yes, that would be too easy. A professional criminal is one of the usual suspects and will be in the focus of the police far too soon. Mystery novels are not about how the police got Mr. X again, they’re about an unusual suspect committing a crime.

18. A crime must never turn out to be an accident or a suicide. That one, I think, goes without saying as well. Mystery stories are about solving crimes, not reconstructing accidents or analysing suicides. That does not mean, however, that a crime is not allowed to pose as an accident or a suicide.

19. The motif for a crime has to be personal. That’s still true today. If a motif is not personal, the story is more fit for a thriller (be it about a serial killer or some political murder). The ‘Why’ is the link between the victim and the culprit.

20. consists of a list of devices never to be used in a detective story, such as the evil twin, a false séance or planted evidence. Only the first in the list, finding the criminal by comparing traces from the crime scene to something the culprit has at his or her disposal (van Dine manages cigarette ash) has to be taken off the list. That’s how modern forensics work. Modern mystery stories have to accept this fact as a fact, but the detective doesn’t have to analyze this clue himself (or herself). He or she can be told.

Twenty rules for writing a mystery story. Some might not really be important today, but they’re still worth considering.