While defining an author’s overall voice can be tricky, it is a bit easier to do so with characters, if they stand on their own. But at times finding the daylight between the author and his characters can be difficult. It used to happen to me when I was younger that people would ask me “But why did you say that?” or “Is that what really think?” which led me to answer “That’s not me, that’s a character,” especially if it the story was in first person.
I will admit that some characters, especially my MCs, start out as idealized versions of myself, that is, the kind of person I would like to be if I were in that situation. However, they are not me and even stories peppered with biographical elements are still not entirely biographical, but fiction, and while I would like to act in certain way, that doesn’t mean I would do so in that kind of situation. It’s hard to separate oneself from the Narrator/MC in first person pov, but doable, if at the end of the day that character stands on his own two feet. If he doesn’t then he is a Mary Sue/Marty Stu which tends to turn off the reader.
In third person it gets a bit more complicated. A character (need not be the MC) may serve as an author’s surrogate, a strawman (political, ideological, philosophical or religious and almost always goes hand in hand with the author’s surrogate, usually as his antagonist to emphasize the correctness of the author’s position), a Mary Sue, anachronistic vocabulary (common in fantasy) or false voice (happens a lot in YA, which is written by adults but populated with characters that are almost always children and teens).
Again, the question is, due these character’s stand on their own two feet, or are they merely hallow constructs echoing the author’s views and voice?
So how do you separate the two?
Purpose and vocabulary are key. Each character must have their own voice and reason for being in the story besides or beyond those stated above. The vocabulary must be appropriate for the age, social group and era in which the character finds himself as well as the particular conditions of the story. Another way is character presence (the “own two feet” thing I talked about earlier). Is the character presence necessary? Does it move the story forward? If the reader stops reading and asks himself why the character is in the story, chances are it is surperflous, especially when the real reason is to serve one of the purposes stated above.
Not to say that any of those roles are inherently bad, if they are part of a deeper characterization or if used for parody. But principal character should be more than puppets for the author. The reader will see the hand going in the back and noticed that only one of you is moving his lips at a time.
Just so you know.
Of course, I haven’t given any real solutions to the problem, because beside saying “Don’t do it!”” I really don’t have any.