Harper Lee wanted the contrast between good and evil to be as explicit as possible within the confines of the context in which her novel, To Kill a Mockingbird, takes place. Atticus Finch is the embodiment of human decency, unfailingly courteous and civil in his discourses. His defenses of Tom Robinson, both before a lynch mob and in a court of law, are invariably rooted in the law and in a larger sense of community and civility. He is, to apply an outdated word, a gentleman. In Tom's trial for allegedly raping Mayella Ewell, the white teenage daughter of the town’s most virulently racist drunk, Atticus knows that the prospects of acquittal are minimal given the fact that Tom is black and Mayella is white. This is the Deep South of the 1930s, and a black man accused of raping a white woman was extremely unlikely to receive a fair trial. Atticus also knows, however, that the justice system (of which he is a part) must function and the trial must proceed. His cross-examination of Mayella, who is lying at the behest of her father, is typical of his demeanor and professionalism. He is direct, but polite. He does not appear condescending, despite the witness’s lack of education, her dismal upbringing, and her obviously false accusations. Note in the following passage the initial exchange between accuser and counsel for the defense:
“Miss Mayella,” he said, smiling, “I won’t try to scare you for a while, not yet. Let’s just get acquainted. How old are you?”
“Said I was nineteen, said it to the judge yonder.” Mayella jerked her head resentfully at the bench.
“So you did, so you did, ma’am. You’ll have to bear with me, Miss Mayella, I’m getting along and can’t remember as well as I used to. I might ask you things you’ve already said before, but you’ll give me an answer, won’t you? Good.”
Contrast Atticus’s polite and professional approach to interrogating Mayella with Mr. Gilmer’s cross-examination of Tom Robinson, the black man wrongfully accused of rape:
“You were given thirty days once for disorderly conduct, Robinson?” asked Mr. Gilmer.
“What’d the nigger look like when you got through with him?”
“He beat me, Mr. Gilmer.”
“Yes, but you were convicted, weren’t you? . . .
“Had your eye on her [Mayella] a long time, hadn’t you, boy?”
“No suh, I never looked at her.”
“Then you were mighty polite to do all that chopping and hauling for her, weren’t you, boy?”
Mr. Gilmer is as disrespectful and unprofessional as Atticus is courteous and professional. Mr. Gilmer knows that the jury is in his hands, a product of centuries of slavery followed by Jim Crow laws and institutionalized segregation. Repeatedly addressing Tom as “boy,” a pejorative word when applied to African American men due to its connection with slavery, is Mr. Gilmer’s way of appealing both to the racism present in the courtroom and to Tom’s sense of inferiority relative to the town’s white population. His use of the highly offensive word "n*****" similarly is degrading and intended to portray the defendant in the most negative light possible in this racist town. His reference to Tom's prior arrest was intended to buttress the stereotype of the African American man as innately violent.
Lee’s contrasting visions for the two lawyers illuminates the vast distinctions between the treatment of whites and blacks. Atticus had to be respectful of Mayella while impugning her testimony; Gilmer wanted to be demeaning to Tom as a way of presenting the accused as worthless and guilty of something, whether that something was rape or simply being black.