sm was.In the book, Atticus tells Scout and Jem, "I'd rather you shoot at tin cans in the backyard, but I know you'll go after birds. Shoot all the bluejays you want, if you can hit'em, but remember its a sin to kill a mockingbird." (pg.***) Boo and Tom were accused by the town for things that they didnt do. It is a sin to kill a Mockingbird that just sings for people and it is a sin to judge people by outside things. The sheriff knew that Boo killed Mr. Ewell but covered it up because it would be wrong to make Boo go through everything that Tom went through even though he was innocent. Tom and Boo were both mocking birds in a way. They never did anything to really hurt anyone and didnt deserve to be shot down by society....