Gangbuster, by Alan Prendergast

Prendergast's compelling 1920s cat-and-mouse legal chase is a ground-breaking account of how Denver's DA took on the Klan and the city's corrupt government.  With skillful storytelling reminiscent of American Midnight, the book investigates the racism, xenophobia, and greed specifically governing the Mile High City a century ago--but that continue to plague regions of this country today.