A while ago I wrote about the problem of how to put characters above suspicion in a murder mystery so that readers could become fond of them. The problem, as I mentioned, is that golden age mysteries loved to try to put the murderer as far above suspicion as possible. However, we need some characters to be actually above suspicion so that we can have an enjoyable story. So, how do we put them above suspicion in a way that the reader can believe? I gave one answer before, but another recently occurred to me.
A reliable way to put a character above suspicion, for the reader, is to tell the reader the character’s thoughts. Obviously this relies on the story seeming to adhere to the spirit of Fr. Knox’s detective decalogue, or otherwise just that the author is honest. An author who would purport to tell us what a character is thinking but leave out the most important things that they’re thinking is just being dishonest, even if they don’t outright lie. So as long as you have the reader’s trust, telling them a character’s thoughts, which are not about the murder at a time when they would be about the murder if the character was the murderer, will enable the reader to trust the character.
This doesn’t need to be done in such a way as to turn the character into a main character, either. Perhaps an extreme example of this might be Caroline Bingley in Pride and Prejudice.
Persuaded as Miss Bingley was that Darcy admired Elizabeth, this was not the best method of recommending herself; but angry people are not always wise; and in seeing him at last look somewhat nettled, she had all the success she expected.
We are not, that I can recall, ever told Caroline’s thoughts before or after (except in the final chapter, which gives a summary of the next few years).
Like all techniques it must be used judiciously, but I think that it could be used well.