“Lemme tell you somethin’ now, Billy,” a third said, “you know the court appointed him to defend this n*****.”
“Yeah, but Atticus aims to defend him. That’s what I don’t like about it.”
This was news, news that put a different light on things: Atticus had to, whether he wanted to or not. I thought it odd that he hadn’t said anything to us about it – we could have used it many times in defending him and ourselves. He had to, that’s why he was doing it, equaled fewer fights and less fussing. But did that explain the town’s attitude? The court appointed Atticus to defend him. Atticus aimed to defend him. That’s what they didn’t like about it. It was confusing.

– Harper Lee

To Kill a Mockingbird, Chapter 16. Scout hears the chatter from court spectators that Atticus had to defend Tom Robinson because he was appointed by Judge Taylor. But he hadn’t told his children that. She is further confused when the chatterers say Atticus aims to put on a defense for Tom and they don’t like this. Atticus wanted to take on Tom’s case because he wants justice to be served and wants to protect people’s rights, and he needs his children to understand how deeply he cares about this. Always the morally principled and excellent father who teaches by example.