I just finished reading Don Winslow's novel "The Force" and can say it's a very entertaining book. It's about a crooked NYPD sergeant who happened to be the top dog in a task force they called "Da Force." The book started out slow, and was a little bit dull with all the background detail, but at the mid point it skidded over into the fast lane and didn't let up until the last page. A good book.
It could be a companion piece with "Blue on Blue," the non-fiction book by Charles Campisi who was the head of IAB at the NYPD for many years. In that book he told stories of snaring crooked cops. It's a good counterpoint to "The Force" and should probably read last as a palate cleanser.
Both of these books were available at the public library in the modestly sized city of Midland, Texas. Otherwise they are available to non-cheapskates for purchase in various formats from Amazon.com.