Boo Radley demonstrates that prejudice was not limited to race. Boo is different, and therefore ostracized. His parents have no sympathy for him, and somehow manage to keep him inside the house so that he has almost no human contact.
Nobody knew what form of intimidation Mr. Radley employed to keep Boo out of sight, but Jem figured that Mr. Radley kept him chained to the bed most of the time. (ch 1)
Atticus tells the children that “there were other ways of making people into ghosts” (ch 1). The family keeps Boo inside because they are ashamed.
The people’s attitude toward Boo varies. Some, like Miss Stephanie Crawford, are ready to pass rumors. Others, like Miss Maudie, want to treat him as human. The fact that most people refer to him as “Boo” is an example of their prejudice.
Lee uses Boo to point out that in a small Southern town like Maycomb, everyone knows everything about everyone. Although there are good things about this, such as everyone helping with the fire, the negative of the fish bowl is that a person like Boo Radley never gets any peace because he is a little different.
Boo Radley is one of the mockingbirds of the story. He is a gentle, shy soul. He only wants to help and be friends, but he is treated poorly by he community because he is different. Boo manages to escape getting shot, because Heck Tate and the Finches realize that he does not want to be revealed.