I've never read Wambaugh tho he published several books.
And MURDERER WITH A BADGE by somebody
Looks like he was a one hit wonder, but its well written. Its about Officer Friendly the really nice serial killer. It starts with a murder a lot like a murder near my home in 1958. Two boys killed a crazy old man near us. He had a fortune hidden away but lived an austere and Spartan lifestyle. The old man in the story had $60,000 his away, Thgeodore my neighbor prolly had as much or more.