Mr. Harry Johnson.
He was a mad dog. Atticus shot him and then Scout and Jem found out that their dad was "One-Shot Finch." The dog represents racism and Atticus shooting him represents Atticus trying to bring down...
Tom Robinson was an innocent black man founded guilty of raping and beating a young girl named mayella.
Atticus had given up shooting because he felt he had too much of an advantage over living creatures to shoot them.
1. Johnson Dog Shooting2. Trial of Tom Robinson3. The Pageant (at the end of the book)Hope that helped?!