Scout is at her observant best during her stay in the courtroom during the trial of Tom Robinson. She sizes up Judge Taylor as being
... like most judges I had ever seen: amiable, white-haired, slightly ruddy-faced, he was a man who ran his court with an alarming informality...
She especially enjoys the way in which the judge would "munch" his cigar without ever lighting it. Scout immediately recognizes when Atticus has caught Sheriff Heck Tate in a mistake.
Mr. Tate blinked again, as if something had suddenly been made plain to him.
She sees that Bob Ewell is no different than the Negroes who live nearby except
... that if scrubbed with lye soap in very hot water, his skin was white.
Scout began to see Mayella very clearly, that Mayella
... must have been the loneliest person in the world. She was even lonelier than Boo Radley...
and Scout sees the direction in which Atticus's questions are going--
Atticus was quietly building up before the jury a picture of the Ewells' home life.
And when Tom Robinson first stood up in the courtroom, Scout quickly saw that
He looked oddly off balance... His left arm was fully twelve inches shorter than his right, and hung dead at his side.