To Kill A Mockingbird by Harper Lee, reveals the harsh truth of how discrimination, stereotypes and double standards govern many communities which are unable to recognize their own narrow-minded bigotry. Maycomb County is typical of a southern town of the era where even the word of the despised Bob Ewell, considered to be "the disgrace of Maycomb for three generations," is preferred over the word of Tom Robinson, purely because Tom is black and Bob Ewell, the supposed victim's father, is white.
Atticus, who defends Tom, but has no illusions as to the outcome, has always brought his children up to respect the opinion of others. He has taught them that everyone deserves fair treatment and especially that, "it’s a sin to kill a mockingbird," because "they don’t do one thing but sing their hearts out for us." Tom Robinson is, effectively, one such example. He never did anything wrong - but only tried to help Mayella Ewell- and yet he will be found guilty, despite the overriding evidence to support his innocence.
Jem is confident that Tom will be acquitted because the evidence is so compelling. Atticus on the other hand, knows that Maycomb County has other priorities and will uphold its intolerant, unjust and racist form of community. Jem is excited that Tom will be cleared and disillusioned when he is not. Jem reflects on the conflicting signals people send out and because of this, he gains perspective and begins to understand Boo Radley's position as he is a person who has also been judged unfairly,"I think I'm beginning to understand why Boo Radley's stayed shut up in the house all this time...it's because he wants to stay inside."