Pegasus Descending - "hard boiled" detective fiction. Lead character is a recovering alcoholic, complicated, well-drawn. The protagonists - and most of the antagonists - in Burke's fiction are more than one dimensional. The best part of his works, though, are that they are set in southern Louisiana, and the author obviously is deeply in love with this part of this state. His descriptions of the bayous are more than half the reason I read him (I'm not a crime/detective fiction person, either) - he makes me see, feel, and even smell them. I'd actually recommend them for that reason alone.
True crime - The Stranger beside Me by Ann Rule. Don't get me wrong - I normally detest Ann Rule, and the "true crime genera" of which she is a major player- but in this book about Ted Bundy,. the man who worked beside her at a crisis line and the monster he became, are fascinating characters. Not for the faint of heart, though.
The Monster of Florence by Douglas Preston and Mario Spezi, another true story, but hard to believe. Spezi is a reporter for a major Italian newspaper, Douglas a major author of detective fiction in the U.S. and Italy, who through happenstance fall in together investigating a serial killer in Florence. The investigation by the Italian police - and army - becomes an international farce involving Satan, alleged child molesters, hired killers - and the arrest of Spezi and the indictment of Douglas. Incredible story, well worth reading (Douglas is an excellent writer) but the Monster is , well, a monster, and the descriptions of his killings are hard to read. He was never apprehended, by the way.
For someone who is not a crime novel fan, I've certainly gone on and on...
Of the three, I couldn't really pick a favorite, of the three crime authors I have read, Burke is my favorite. Of non-fiction, Spezi and Preston.