Concerning the issue of racism, the following quotes reveal how deep Maycomb has drawn into the racist prejudices and ignorance:
Why reasonable people go stark raving mad when anything involving a Negro comes up, is something I don't pretend to understand...
(Chapter 9, p. 93)
In this quote, Atticus shares his confusion with his brother, admitting that the case of Tom Robinson is about to raise the storm of meanness and anger among the town people. With this words, he shows that such situation is not new or unpredictable. The southern states haven’t change much in their moods regarding African Americans. However, Atticus stands firm resisting the traditionally racist views in his town.
Scout," said Atticus, "nigger-lover is just one of those terms that don't mean anything—like snot-nose. It's hard to explain—ignorant, trashy people use it when they think somebody's favoring Negroes over and above themselves. It's slipped into usage with some people like ourselves, when they want a common, ugly term to label somebody.
(Chapter 11, p. 113)
According to Atticus, the word ‘nigger-lover’ is used just to abuse people who don’t share the racist views. It labels not the people to whom it is said, but rather those who say it. It marks the people who feel the supremacy towards the African Americans. To be a nigger-lover means to treat black as equal, while it goes against the public idea of what is right.
Lula stopped, but she said, "You ain't got no business bringin' white chillun here—they got their church, we got our'n. It is our church, ain't it, Miss Cal?
(Chapter 12, p. 121)
The character’s quote indicates the racial division that works against both sides: white people don’t belong to the black people’s places either. Being discriminated, the black community also developed a form of racist views that target white inhabitant of the town. Jem and Scout for the first time face the reverse racism in the church of a black parish where Calpurnia has brought them. Yet, it turns out to be fragmentary, while the most of the black people in the church welcome the kids.
She was white, and she tempted a Negro. She did something that in our society is unspeakable: she kissed a black man. Not an old Uncle, but a strong young Negro man. No code mattered to her before she broke it, but it came crashing down on her afterwards.
(Chapter 20, p. 206)
These words Atticus proclaims in the court, trying to convince the jury to find Tom Robinson not guilty. He shows the motives of the Ewells lie, demonstrating that Mayella is ready to see Tom’s death rather than to admit that she was trying to tempt him. At the same time, Atticus questions the public code, according to which to feel a temptation to the black man is the disgrace that the person cannot live with.
Which, gentlemen, we know is in itself a lie as black as Tom Robinson's skin, a lie I do not have to point out to you. You know the truth, and the truth is this: some Negroes lie, some Negroes are immoral, some Negro men are not to be trusted around women—black or white. But this is a truth that applies to the human race and to no particular race of men. There is not a person in this courtroom who has never told a lie, who has never done an immoral thing, and there is no man living who has never looked upon a woman without desire.
(Chapter 20, p. 207)
This is the fragment of the Atticus’s closing speech in the court. He appeals to the jury, trying to bring them to senses. He emphasizes that there is not a drastic difference between the people of different skin color. Yes, there are black men with the vicious intentions, but they are not determined by their race. That’s just the questions of every particular person and his or her qualities. To stress the thought he says that there are basically no saint people, among the whites as well. So there is no reason to think that the white people are better that the blacks in any way.
There's something in our world that makes men lose their heads—they couldn't be fair if they tried. In our courts, when it's a white man's word against a black man's, the white man always wins. They're ugly, but those are the facts of life.
(Chapter 23, p. 223)
These words Atticus says to his son, explaining why he thinks he doesn’t have many chances to win Tom’s case. He shows Jem, how things are, without trying to hide something from him. What is important for Atticus is to make Jem understand how ugly and tragic the prejudices can turn to be. People who share the racist views don’t leave them at home, no. They keep influencing on everything they do. The same is applicable to the people who work in a court.
As you grow older, you’ll see white men cheat black men every day of your life, but let me tell you something and don’t you forget it—whenever a white man does th at to a black man, no matter who he is, how rich he is, or how fine a family he comes from, that white man is trash .
(Chapter 23, p. 223)
This 'prejudice quote' expresses one of the key agendas of the book. No matter what social status you have, if you take advantage of the weakness and vulnerability of other people, it shows that in fact, you are worth nothing. Scout notices that it is not usual for Atticus to call somebody trash. Yet, he finds the everyday racism totally unacceptable and he allows himself to be downright saying this.