Within the framework of O'Connor's Christian concept of "grace," that a divine pardon is granted by God simply for the asking, the Misfit must be the one held morally responsible for the killing of the six family members. For, it is the petty, selfish, and forgetful grandmother who attains grace at the end of "A Good Man is Hard to Find" as, at the moment of her death, she reaches out to the Misfit exclaiming, "Why, you're one of my children."
In the context of O'Connor's narratives, grace is something often undeserved, a force outside of the character that generates an epiphany. The grandmother has such an epiphany and receives grace as her spiritual blindness is removed.
I'll say Flannery O'Connor. Ultimately, it is only she who controls the LACK OF MORALITY in her fiction. She would not want us to choose either the Misfit or the grandmother since all her characters are doomed.
O'Connor once said:
This is a generation of wingless chickens, which is what Nietzsche meant when he said...
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