The song JD Crowe is performing was originally a Cliff Carlisle song (part of the Grand Ole Opry's Carlisle Brothers) called "The Girl in the Blue Velvet Band." It has been memorably covered by Bill Monroe and others. The just ending you mentioned was in the original: "They sent me to San Quentin for stealing/Lord knows I;m an innocent man/But the guilty one, now she lies dying/the girl in the blue velvet band." Beware, ye country folk that long for life in the city!