First thing I thought of was "Long Black Veil," not really a folk song (composed for the Nashville country-music industry in the 1950s), but deservedly popular among folksingers types and, well, singers of all stripes.

Writing the narrative from the point of view of the dead person is a time-honored angle, but in this case, the deceased voice is not the murder victim, but rather the falsely accused perpetrator who bit his tongue and died on the scaffold rather than hurt someone else by revealing his alibi ~ that's real tragedy.

Also coming to mind: Mississippi John Hurt's "Louis Collins," recently discussed here. The refrain "Angels laid him away" is pretty poignant.