Chapter 17: Mr. Gilmer, the prosecuting attorney, calls Sheriff Tate to the stand first. Tate describes how Bob Ewell called him to the scene of the crime, his own house, one afternoon. Upon arrival, Tate recollects, he finds Mayella Ewell, Bob's daughter, badly beaten with marks around her neck and bruises about her face especially around her right eye. His testimony makes it sound as if someone used both hands to grab Mayella around the neck and strike her in the face at the same time. Atticus's questioning reveals that no one, including Tate, ever contacted a doctor. Everyone had simply assumed that a rape had occurred due to the nature of Mayella's external injuries.
Next Mr. Gilmer calls Bob Ewell to the stand. Bob explains the story exactly as Tate explained it. He adds nothing new to the prosecution's story except that he claims he saw Tom Robinson beating Mayella. He didn't chase Tom, he says, because he stays in the house to help Mayella. Upon cross-examination, however, Atticus shows that Bob is left-handed and that he didn't call a doctor either. Atticus's questions embarrass Bob Ewell who sneers and bristles when Atticus speaks to him.
Chapter 18: Mayella takes the stand next. To Mr. Gilmer's questions Mayella responds that she asked Tom Robinson into the yard to help her chop up a chiffarobe (a wooden dresser). She claims that she had never asked Tom onto the property before even though Tom passes the Ewell property everyday on his way to work. As Mayella went inside to fetch a nickel for Tom, she states, Tom followed her into the house where he raped and beat her. To Atticus, Mayella acts like a hostile witness, she thinks Atticus is making fun of her because of the respectful language he uses to address her. Mayella reveals to Atticus that Bob Ewell is a good father except when he drinks and describes the poor conditions in which she and her seven siblings live. When Atticus asks Mayella to identify her attacker she points to Tom Robinson who stands to face her. When Tom stands, however, we realize that his left arm, having been mangled in a cotton gin when he was twelve, hangs limply to his side. To Jem and Scout it is obvious that Tom could not have attacked Mayella with only his right hand. Mayella leaves the stand defiantly.