Lee neatly structures her novel around a dual plot and dual Themes; the novel is evenly divided into two parts. In her graceful, understated style, Lee weaves together a story about two children growing up in a small southern town, and a story about the children’s father, a white attorney who defends a black man unjustly accused of raping a white woman. Because both stories involve Jem, Scout, and Atticus, Scout’s first-person narration, with its focus on the development of these three Characters, unifies the different story lines.
The narrator’s emphasis on Jem is particularly significant to the structure and meaning of the story. Lee creates in Scout an immensely likable, funny character, but she invests Jem with the depth and literary complexity of a protagonist. Each section of the book begins and ends with a description of Jem as he matures and changes. Scout begins her narrative with the statement: “When he was nearly thirteen, my brother Jem got his arm badly broken at the elbow.” The rest of the story follows from this simple revelation, and by the final chapters, when the injury actually occurs, the broken arm carries symbolic significance.
Through much of part 1, Jem is a child who plays make-believe games with Scout and Dill, but toward the end of the first section, he has begun to recognize the difference between right and wrong, good and evil. Scout’s narration reflects this development; she begins part 2 by noting: “Jem was twelve. He was difficult to live with, inconsistent, moody.” Hence, Scout sets the tone for the section of the novel that deals largely with the trial of Tom Robinson; just as Jem is entering a difficult stage, learning to confront conflicting emotions and beliefs, so too are the people of Maycomb feeling the tension of a trial that will shake the foundation of their racially-divided town. Near the end of the novel, Bob Ewell, who represents the backwardness and evil of prejudice, tries to kill Jem and Scout in a vengeful attempt to hurt Atticus. Jem’s arm is broken during the attack, symbolizing the pain and disillusionment he has experienced while learning about Boo Radley and witnessing the Robinson trial.
Jem survives the attack but carries a permanent scar, a symbol of the disabling power of hatred and injustice. Scout says that as a result of his injury that night, Jem’s left arm is “somewhat shorter than his right; when he stood or walked, the back of his hand was at right angles to his body, his thumb parallel to his thigh.” In this way, Jem shares a bond with Tom Robinson, for Robinson’s left arm is also shorter than his right. As a result of an accident involving a cotton gin, he is permanently crippled, and as Atticus argues at his trial, he is therefore physically incapable of beating Mayella Ewell in the manner that she describes. Yet Robinson’s most damning handicap proves to be his race. Jem’s broken arm serves as a reminder of this fact, and Lee implies that Jem has been irreparably changed as a result of Tom Robinson’s trial.
Lee also suggests, however, that Jem’s disillusionment is not permanent and that he will grow up to be as fair-minded and compassionate as his father. Atticus acts as a guardian of justice throughout the novel, and Lee symbolically ends the story with the image of Atticus watching over his children. Scout’s final passage states that Atticus “turned out the light and went into Jem’s room. He would be there all night, and he would be there when Jem waked up in the morning.”