Sheriff Heck Tate sits forward intently in the witness chair with his hands touching each other between his knees as he listens very carefully. Clearly, he is determined to perform well as a witness.
As he looks down to avoid distraction, Sheriff Tate is questioned by Mr. Gilmer, the prosecutor. Tate testifies that Mr. Ewell came in to his office on the night of November twenty-first and demanded that the sheriff get out to his house quickly. When he did so, Tate found Mayella Ewell lying on the floor, displaying signs of having received a strong beating. The sheriff lifted her to her feet, whereupon she washed her face in a bucket, and then seemed to be all right. Tate asked her who had hurt her, and Mayella replied that Tom Robinson had done these things to her. He then asked Mayella if Tom had taken advantage of her, and she affirmed that he had. So, the sheriff "took him in." That is, he arrested Tom.
When Atticus is allowed to cross-examine, he asks the sheriff if he called a doctor. Tate replies that he did not. Atticus asks him why no doctor was summoned, and Mr. Tate replies that he did not think calling a doctor was necessary. He adds that Mayella was simply bruised and had a black eye; it was her right eye. Suddenly, however, he seems to realize something, and he turns and looks around at Tom Robinson. Atticus asks the sheriff to repeat what he just said. "It was her right eye, I said," Sheriff Tate repeats. Those sitting in the balcony section whisper among themselves after this statement.
This last statement causes Jem to smile and say something about "corroborating evidence." The fact that Mayella was struck brutally in the right eye is the kind of evidence that Atticus needs in order to discredit Bob and Mayella Ewell and prove Tom Robinson innocent. A bruised right eye would suggest that Mayella was beaten by someone left handed—but Tom's left arm, injured when he was a child, is essentially useless to him.
In Chapter 17, the first witness called to the stand is Sheriff Tate. When Mr. Gilmer, the solicitor, asks him to state the events “in his own words,” Sheriff Tate says that he was “fetched” by Mr. Bob Ewell when he was leaving his office on the night of November 21st. Mr. Ewell was very excited and said that “some nigger’d raped his girl.” (17.223) When Sheriff Tate arrived, he found Mayella lying in the middle of the front room. After helping Mayella to her feet and cleaning her face in a bucket, Tate was told by Mayella that Tom Robinson was the perpetrator. Tate asked Mayella if Tom beat her and took advantage of her. After Mayella confirmed and identified Tom Robinson, Sheriff Tate arrested him. Atticus asks Sheriff Tate if he called the doctor, but Tate says he did not because it wasn’t necessary. Sheriff Tate then is asked to describe Mayella’s injuries. Tate says that she was beaten around the head and had bruises coming in on her arms. (17.224) When Sheriff Tate mentions that Mayella had a “black eye comin’,” Atticus asks him which eye he is referring to. Sheriff Tate initially tells Atticus that it was her left eye that was bruised, but then recalls that is was actually her right eye. Tate continues to describe Mayella’s other injuries, which include bruised arms and finger marks around her neck.