“You work with what is given to you. You arrange the puzzle pieces taken from the nonfiction box without reaching over into the fiction box, as tempting as it may be. You do your best to pull up honest memory. Though we know memory’s weakness, at least don’t lie about what you think you remember. When you are not sure, you tell the reader. When you want to change something, explore why you want to change it. Fiction approaches a certain sort of truth, and thank goodness we have fiction, but it is not the same truth that nonfiction attempts. Know the difference. As a nonfiction writer, you will surely make mistakes, get things wrong, remember poorly, but to do it knowingly, that’s crossing the line.”
Source: Dinty W. Moore, “What is Given: Against Knowingly Changing the Truth,” part of a worthy exchange with Jill Talbot on the Brevity blog.