The Attorney General prosecuting the case demands that the jury sentence Charles to death. He calls a witness, the "unimpeachable patriot" John Barsad, whose testimony implicates Charles as a spy. However, on cross-examination Stryver reveals Barsad to be a gambler and brawler and a generally untrustworthy witness. Stryver similarly is able to raise questions about the motivations of another witness, Roger Cly, Charles's former servant.
The prosecuting attorney foreshadows the later prosecutors in France who will bend the truth to seek an execution. Ironically, Charles is accused of spying while John Barsad and Roger Cly (who are later revealed to be actual English spies) are presented as "unimpeachable" witnesses.
Mr. Lorry, Lucie, and Dr. Manette are each called to testify: they had all met Charles aboard ship on their way back from Paris five years earlier. Lucie explains how Charles helped her care for her father, swaying the jury in Charles's favor. But she then accidentally turns the court against Darnay. How? First she admits that Charles was traveling with other Frenchmen and carrying lists. Second she mentions Charles's joking comment that George Washington's place in history might one day match that of England's King George III.
Another irony: as will be revealed later, Charles's "suspicious" activities are actually his humanitarian efforts to help his impoverished tenants in France. He is putting himself in danger to help others. His comment about George Washington (who was leading the American Revolution at the time) indicates that he has revolutionary sympathies.
Later, while Mr. Stryver is unsuccessfully cross-examining a witness who has been called to identify Charles, Carton hands Stryver a note. After reading from the note, Stryver forces the court to notice the striking resemblance between Charles and Carton, shattering the witness's credibility.
Besides serving an important role in the plot, the uncanny resemblance between Carton and Charles links them and sets them up as doubles to be compared and contrasted.
The jury goes to deliberate. Carton continues to look bored, stirring only to order help when he notices Lucie start to faint. Finally, the jury returns from its deliberations with a verdict of not guilty.
Carton's boredom identifies him as uninterested in the world and empty. Only Lucie seems to interest him.