In what chapter of Harper Lee's To Kill a Mockingbird does Scout say the following: Don’t see how any jury could convict on what we heard and...

In Harper Lee's To Kill a Mockingbird, it is actually Jem, not Scout, who says the following to Reverend Sykes toward the end of Chapter 21, approximately 3 or 4 pages from the end:

[Atticus] is not supposed to lean, Reverend, but don't fret, we've won it ... Don't see how any jury could convict on what we heard--." (Ch. 21)

Jem says the above to Reverend Sykes while sitting in the colored...

In Harper Lee's To Kill a Mockingbird, it is actually Jem, not Scout, who says the following to Reverend Sykes toward the end of Chapter 21, approximately 3 or 4 pages from the end:

[Atticus] is not supposed to lean, Reverend, but don't fret, we've won it ... Don't see how any jury could convict on what we heard--." (Ch. 21)

Jem says the above to Reverend Sykes while sitting in the colored balcony in the courtroom as they wait for the jury to return with its verdict. While they wait, Jem and Reverend Sykes discuss the trial. Scout, Jem, and Dill had just returned to the courtroom after having gone back to the Finch house for their evening meal. Jem is eager to find out from Reverend Sykes what he had missed. Reverend Sykes gives his own description of the portion of Atticus's closing remarks that the children had missed. According to Reverend Sykes, Atticus's closing remarks were "mighty fair-minded," and it seemed to Reverend Sykes that Atticus had leaned in favor of acquitting Tom Robinson during his closing remarks.

Jem's response to Reverend Sykes shows his naive confidence in the court and jury system. Jem knows full well that all evidence revealed in the case was only circumstantial evidence, and all pointed toward the guilt of Bob Ewell and the innocence of Tom Robinson. Yet, Reverend Sykes must warn Jem not to be overly confident, saying to Jem one of the more important lines in the book that underscores the theme of racial prejudice:

Now don't you be so confident, Mr. Jem, I ain't ever seen any jury decide in favor of a colored man over a white man. (Ch. 21)

When the jury returns with its guilty verdict, proving Reverend Sykes correct in his doubts, Jem is shaken to the core because he now sees mankind's true capabilities of having an evil nature. Jem becomes so angered by the unjust verdict that he behaves very differently throughout the rest of the book and must reach new conclusions about mankind.