Atticus tried to point the guilt in another direction, whom did he suspect?
Atticus suspects Mayella's father, Bob Ewell, is to blame for her injuries. When Mayella is on the stand, Atticus questions: "What did your father see in the window, the cirme of rape or the best defense of it? Why don't you tell the truth, child, didn't Bob Ewell beat you up?" (Ch 18)
Bob Ewell was the person who had hit Mayella