One of the decisions that a mystery author needs to make is which point of view to use for a mystery. Usually, we authors choose first or third person. Point of view is an important aspect of a mystery novel, at least for me, because it determines how much is going to be revealed to the reader.
Some authors choose the first person point of view. Michael Collins (AKA Dennis Lynds) used first person to tell his stories of private detective Dan Fortune. Janet Evanovich does the same thing with her Stephanie Plum series. So does Patricial Cornwell in her Kay Scarpetta series and Laurien Berenson in her Melanie Travis series. The beauty of using first person is that the events unfold for the reader just as they unfold for the character whose viewpoint is the focus of the story. In many cases, (like the examples above), that character is the sleuth. The advantage to this is that the reader can find clues, sort them out and make sense of them just as the sleuth does.
Some authors use the first person even more creatively. For instance, Agatha Christie used it in an interesting way in Murder in Mesopotamia. There, the story is told from the point of view of a nurse who's hired to attend the wife of the chief archeologist on an important dig. The nurse isn't the sleuth; in fact, Hercule Poirot is. She's not Poirot's usual scribe, either; Captain Arthur Hastings has that honor. She writes the story because, as she says, she was "in it all, and yet an outsider, so to speak." Christie also uses the first person brilliantly in The Murder of Roger Ackroyd, which I recommend if you haven't read it, and which was actually criticized harshly when it was first published. It wasn't at all a conventional mystery, and some thought Christie wasn't "playing fair."
Many authors (myself included) use third person. The number is so great that I won't list any here. I won't speak for other authors, of course, but I use third person for several reasons. The most important reason is that I want to share several people's viewpoints with the reader. I want the reader to know what different people might be doing at the same time. I also want the reader to see how the events in the story affect different people. It's much harder to do that if one uses first person.
I also use third person because in my novels, although Joel Williams is the sleuth, he doesn't solve crimes by himself. He works with the Tilton, PA police and he learns things from more than one character. Since several people have pieces of the puzzle in my novels, I like the reader to see how those other people think, to find out what happens to them that Williams might not know about (at least at first), and to follow them throughout the novel. That's hard to do, too, if one writes using the first person.
Even if one writes in third person, though, it's still important to keep in mind what the character is probably experiencing and thinking. A story isn't believable if the characters act in unbelievable ways, given what the reader has come to expect of that character. That's why it's important, at least to me, that point of view also take into account the character's personality, background, and so on.
In one very creative use of point of view, Agatha Christie actually uses both first and third person. In The ABC Murders, the novel's point of view is divided between first person (the chapters that are Captain Hasting's personal narrative) and third person (not from Captain Hastings' personal narrative). I consider that one of the most effective uses of point of view I've encountered, actually. It gives the reader the broad perspective of third person, yet focuses on the clues as Captain Hastings learns about them. For this reason alone, I recommend it as a very effective use of perspective.
Which sort of point of view do you like? Do you prefer first person? Third person? Something else? Why?