How is fear used in "To Kill a Mockingbird"?
For example, fear is used to scare the children from the Radley place; fear is used to intimidate Atticus in the scene at the jail (the "mob"; fear is used in the trial. (mayella's fear of atticus/ tom/ father)
An instinct of survival, fear is a response to perceived danger. This danger can be physical or psychological, and it often derives from a lack of understanding or from a sense of being threatened.
Lack of Understanding
Since there are tales about the mysterious Arthur Radley who never leaves his house, there is a fear that is generated in the minds of people. Having heard Miss Stephanie's tale that Boo "drove" a pair of scissors that he was using to cut some articles from the newspaper into his father's leg as he passed before him, Jem and Scout feel trepidation whenever they are near the Radley house. And, since he has supposedly appeared at Miss Stephanie's window at night, "Boo" Radley is feared as though he were a spirit who moves about mysteriously. People fear he may come near them because they do not really understand the nature of Arthur Radley.
Fear also exists in the hearts of those who feel themselves threatened.
The mob at the jailhouse threatens Atticus with their numbers along with their attitudes and aggression. However, once this aggression is diffused by Scout's influence upon Mr. Cunningham, the fear is removed.
Certainly, after already having received a beating from her reprehensible parent, Mayella testifies falsely against Tom Robinson from fear of her father. A racist himself, Bob Ewell does not want people to think that Mayella made sexual advances toward a black man. In addition, Mayella fears Atticus, who might expose her lies. Also, there was a law against miscegenation in Alabama on record until 1967, and Mayella may fear retribution from the law.
Reflective of the 1931 trial on which Harper Lee based her trial in the novel, Mayella's act of accusing Tom seems similarly motivated to the action of one of the two women on the train with nine black men in Scottsboro, Alabama.
[The lawyer for the Scottsboro boys, Samuel Leibowitz] proposed that Price made up the charge (of rape) to protect herself and Bates . . . . Leibowitz speculated that the young women feared they would be arrested for vagrancy or for being hobos in the company of the black youths. (PBS)
Similarly, when Bob Ewell appears and sees Mayella with Tom inside their shack, Tom Robinson runs from the fear of the anti-miscegenation law (Jim Crow was also still in effect). While he is on the witness stand, Tom tells Atticus, who asks him why he ran from the Ewell place:
"I was scared, suh."
"Why were you scared?"
"Mr. Finch, if you was a n*****r like me, you'd be scared, too....I's scared I'd be in court, just like I am now."
Clearly, then, fear is a strong response in some of the characters of To Kill a Mockingbird.
Fear is used to show narrow-mindedness and ignorance. The children are only afraid of the Radley house when they are ignorant of the true nature of Arthur Radley; as long as he's "Boo", he's a feared entity. When Scout, through her simple recognition of Walter Cunningham, Sr., breaks a mob down to individula people. They were no longer a group with the power to intimidate; they were individuals whose connection was their ignorance. The ignorance shown by the Ewells in their hatred of blacks is actually a fear - the Ewells fear what they do not know. The same is true for many of the people in the town and countryside around Maycomb: they fear what they don't understand and they don't understand a race other than their own. In chapter 24, when the women at Aunt Alexandra's tea discuss their "coloreds" and how they now fear them, it is ignorance speaking. Mayella is afraid of Atticus because she is not accustomed to anyone treating her with respect. Harper Lee wants the reader to see that once ignorance is removed, so is fear.