Find the Motive, Find the Killer!
by Stephen D. Rogers

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I'm not sure whether the title of this article is some classic mystery quote but it very well could be. After all, motive is one of the three legs of any successful prosecution: motive, means, and opportunity. Each must be discovered and each must be proved.

If you'd rather publish than prosecute, however, your task is both easier and harder than the prosecutor's. On one hand, you get to make up the killer's motive and then create the facts to support it. On the other hand, you have to develop a motive for every single character.

Everybody Wants Something!

In bad mysteries, motive often serves merely as a tease. Three people gained by the shopkeeper's death. Which of them pulled the trigger?

In good mysteries, everybody has a motive for everything they do. They aren't puppets dancing to the tune of the plot, cardboard characters pasted on stereotyped situations. They're living people with demands and desires.

The Killer: Obviously, the killer had a reason for wanting the victim dead (or the secrets stolen or the convenience store robbed). Unless the victim is random, the killer and the victim had a shared history. Even a random victim probably had some quality that triggered the killer's descent into action.

But questions of motive go beyond the basic "Why I killed the deceased:"

Some of these questions may seem simplistic. The killer lies because prison doesn't sound like fun. There's nothing wrong with easy answers so long as the character comes to them and acts accordingly.

The Victim: Very few people want to be murdered. It lacks something both as an immediate and a long-term goal. Why, then, does the victim act in such a way as to generate enough antipathy to cause homicide to happen?

The Investigator:

The Sidekick: Investigators are often assisted by a sidekick who provides anything from special knowledge to comic relief. Why do they put themselves in this situation?

The Witnesses:

The Experts: Investigators often depend on information gleaned from outside experts or merely-the-clerk office workers who have access to sensitive information. Why do these people take the time (and often risk disciplinary action) to offer assistance? Why did they chose their current career in the first place?

The Suspects:

The Assorted Others: Not everybody in a mystery is a force for good or evil. Many are simply minor characters such as waitstaff, taxi drivers, and hotel managers. These are the players who keep the fabricated world revolving. Some writers prefer not to develop these characters too richly for fear they'll steal the show or be accused of not living up to their billing by acting important and then never appearing again. If you do decide to color your minor characters, focus on their desires rather than the usual blemish, twitch, or accent that often attempts to double for characterization.

If animals are driven by biological instincts, human beings are driven by wants and desires and you can use this fact to improve your mystery by creating characters who live and breath. Once you understand your characters, however, you don't need to include their psychological profile to justify their choices. Simply knowing why your characters do what they do will allow you to select words that impart that knowledge to the reader.

For More Information:

Pop over to your nearest used bookstore and search for psychology and sociology textbooks. If possible, take a college or adult ed class on either of the topics. For all the coursework IÕve completed, nothing has been more valuable to my writing than an evening Introduction to Psychology class.

If you cringe at the thought of reading a textbook, you might want to try The Writer's Guide to Character Traits : Includes Profiles of Human Behaviors and Personality Types, by Linda N. Edelstein.

Find Out More...

What Do Your Characters Want? (Part One) - Victoria Grossack

What Do Your Characters Want? (Part Two): How to Use Characters' Goals to Move the Plot - Victoria Grossack

Copyright © 2002 Stephen D. Rogers
This article may not be reprinted without the author's written permission.

Stephen D. Rogers has published mysteries in magazines ranging from Plots With Guns to Woman's World, multiple anthologies, and several non-mystery markets. He is a graduate of the Framingham Police Department's Citizen Policy Academy and a member of Mystery Writers of America, Private Eye Writers of America, and the Short Mystery Fiction Society. Visit his website at


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