The speaker is someone reporting what Gram said when she was put on trial. A lawyer wanted to call her crazy, but she refused the label and offered her own explanation: her husband, "Daddy," was a shape-shifter, and she shot him when he turned into a bear. She blames his Martin ancestry, which she links to restlessness and heavy drinking, as if the drinking were a way of coping with the strain of never knowing what you might become.
What stands out is her calm. She speaks of the killing in a matter-of-fact, almost folksy voice, even saying she would have fired knowing it was him. The mood is eerie but oddly dry, mixing myth with courtroom talk. The ending is blunt and sad: jailed for her honesty, she hated being "cooped up" and died within a couple of years. The poem seems to ask who gets believed, and what it costs to tell your own truth.