Confessions of an Undercover Cop by Ash Cameron
I really enjoyed this. Short chapters, a no-nonsense style, all true life. Some tales were funny, some sad, some poignant and a few shocking. What shone through was the author's love of her job and the people she policed. It's not a thriller - by 'undercover' she means in plain clothes - but it's an insight into the reality of modern-day policing.
I loved it and learned from it.