For the past year or so my wife and I have been doing a set of traditional American murder songs (songs sung in America but not necessarily originating in America.) Going for as much diversity as possible, here's what we include:

"Pretty Polly"
"Sam Hall"
"Banks of the Ohio"
"Duncan and Brady"
"StaggerLee" (John Hurt version)
"Leaving Home" (a version of Frankie & Johnnie)
"Whitehouse Blues"
"Philadelphia Lawyer"
"Jesse James"
"Bill Martin and Ella Speed"