Scout is no novice to seeing Atticus in action in the courtroom, but the trial of Tom Robinson and the fallout that comes afterward changes her life forever. Scout recognizes early on what the jury can never admit: that Tom could not have physically committed the crimes of which he is accused, and he is found guilty simply because he is black and his accusers are white.
... in the secrets courts of men's hearts Atticus had no case. Tom was a dead man the minute Mayella Ewell opened her mouth and screamed. (Chapter 25)
Her meeting with Dolphus Raymond during a break in the trial reveals that the rumors about "this sinful man" are not true. It opens Scout's eyes once again that appearances can be deceiving. Such is not the case with Bob Ewell, who is every bit as evil as he appears to be in court. Scout worries that Atticus may be in danger, but she and Jem never consider that Bob will come after them. Bob's attack is the most important action affecting Scout's loss of innocence, and Boo's arrival on the scene further opens Scout's eyes that things are not always what they seem in Maycomb. Standing as if in Boo's shoes and looking out upon her neighborhood through Boo's eyes give her a whole new perspective.
Atticus was right. One time he said that you really never know a man until you stand in his shoes and walk around in them. Just standing on the Radley porch was enough. (Chapter 31)