Characters: First Name or Last?

by L.J. Sellers, author of provocative mysteries & thrillers

This is why my novel is taking so long. 

This question comes up dozens of times while I’m writing a novel. Almost every character is given two names (and sometimes a nickname), but what you do you call them most consistently? First name or last? Does their gender and/or role in the story dictate which treatment they get?

I was reading a John Sandford novel recently and I noticed patterns that made me wonder how authors make these choices. There’s a paragraph in which the mother and father of a murder victim are mentioned. Sandford refers to all three by last name, Austin. It’s quite confusing.

In later paragraphs—with the mother, who has the most prominent role of the three—Sandford rotates, sometimes calling her Allyssa and sometimes Austin. This was also confusing, because I’d only met her a few pages back.

Are all novels this messy with names and am I just now noticing because I have to think about these choices when I write stories?

For me, to avoid confusion in family situations, I call everyone by first name and have the detectives refer to them in dialogue by first name or both. Even reporters do this in news stories for clarity.

My main character is Wade Jackson, but everyone calls him Jackson, including me, the narrator. And Jackson, a homicide detective, calls almost everyone he encounters—coworkers, suspects, and witnesses—by their last names. Because this is realistic on the job. Only his daughter and girlfriend get first-name treatment. Young female victims in his cases get first-name treatment too.

The big question for me now is a new character I’m introducing in the Jackson story I’m writing. Everyone else thinks of her as Agent Rivers, so to be consistent, she should be Rivers during her POV. But this character is going to come back in another series and leave the FBI. At which point, I want to call her by her first name. So I’m tempted to start out that way too, so I don't confuse my readers by calling her Rivers in this book, and say, Carla, in the next. But will anyone even notice?

I’m sure styles vary from genre to genre. But in crime fiction—with cops, FBI agents, and private investigators as main characters—I think most coworkers, suspects and witnesses get the last name treatment, while family and friends get first names. I wonder how much it depends on the gender of the writer.

Writers: Do you have guidelines for these decisions? Or do you just wing it? Do you rotate, calling your character Jim, Jimmy, and James? And sometimes by his last name, Shoehorn, just to keep readers on their toes?

Readers: Do you have a preference? Do you like first names or last names better? Does it bother you when writers go back and forth and use different names for the same character?