The mockingbirds in this story were the innocent victims. Tom Robinson is one of the mockingbirds. Although Tom Robinson was probably innocent, the court declared him guilty because of his race. Tom Robinson is a Negro so when he was convicted of raping Mayella, all the whites wanted him to be convicted. The mockingbird represents Tom Robinson because it is a sin to kill mockingbirds and innocent people. Tom Robinson lost all hope because he got convicted, so he went and got himself killed, thinking there was no other way out. In the end, Tom Robinson died because of the unfair trial. Killing him was sinful, just like killing mockingbirds.
Another one of the mockingbirds in this book is Boo Radley. When Boo Radley went to defend Jem and Scout from Bob Ewell's threat, Bob Ewell was mysteriously killed. When Atticus was talking to the sheriff about who killed Bob Ewell, Atticus was thinking about bringing the case to court. However, the sheriff said that to bring Boo Radley, a shy person to court for something he didn't do was as bad as killing a mockingbird. Boo Radley is an innocent person who never wished to harm people. Yet everyone goes and assumes that he is a crazy person who wants to kill everyone.
The mockingbirds' in the story have all suffered because of other people's sinful actions. Boo Radley and Tom Robinson both have horrible life stories and memories. They both never had any intention of hurting the other people in their society. The other people in society thank them by hurting and killing them intentionally.