James Holding 
Cop-Killer [EPUB ebook] 

Pacing the streets of the South Side in the dark, dangerous, dragging hours before dawn, Kangaroo Kelly would often feed himself cheerfully this little morale booster: “Any of these mugs rub me out, even by accident, they’re dead, too. And they know it. For there’s six hundred cops in this town who’ll get them for it if it takes a hundred years. I’m a cop. And you don’t kill cops. Unless you want a fast ticket to hell yourself.”