The trial begins with Sheriff Heck Tate testifying about the day in which he is approached by Bob Ewell, who accuses Tom Robinson of raping Bob's daughter, Mayella. Atticus determines that Mayella was never checked by a doctor to establish the evidence of rape, and he also establishes that Mayella was beaten on the right side of her face--probably by a left-handed man. During Bob's testimony, he claims to have witnessed the attack, and Atticus shows that Bob writes with his left hand. Atticus manages to trap Mayella into contradicting her own testimony: She first claims to have been attacked by Tom, but then says that
"I don't recollect if he hit me..."
Atticus also presents the possibility that Bob may have previously beaten his daughter when he was drunk. Tom claims to have never touched Mayella; instead, it was she who attacked Tom--hugging and kissing him inside the Ewell house. Tom also claims that as he ran from the house, he was met by Bob, who threatened his daughter with the words
"... you goddam whore, I'll kill ya."
To Jem and Scout, it seems obvious that Tom could not have committed the crimes of which he is accused, since Tom has a crippled left arm with a "shriveled" hand. But the jury does not believe Tom, and they return with a guilty verdict. As Atticus leaves the courtroom, Tom's black friends in the balcony stand in unison to honor the man who so staunchly defended Tom Robinson.