It's possible you might be thinking of:
* Charles Todd, the pen name of the writing duo Charles Todd and Karen Kessler. They've written a popular series featuring Inspector Ian Rutledge, set in post-WWI England.
* Charles Todd (no relation), a writer who has published several mystery novels, including the Max Hunter series and A Gathering of Shadows.
Please double-check the name or provide more information about the author you're interested in. This will help me find the correct answer.