Faith and race play big roles in the history of Charleston. In the stories the city tells itself about itself, Charleston joyfully celebrates the former, and rather impressively obfuscates the latter. That unacknowledged history coursed through the murder trials of Dylann Roof and former police Officer Michael Slager this month. The cases were different in important ways and ended that way — Slager’s jury couldn’t reach a verdict; Roof was convicted. But both came to be shaped by the politics of forgiveness, in which each case could be treated as tragedies that existed outside of any history that required acknowledgment.