I say guilt, gentlemen, ...

I say guilt, gentlemen, because it was guilt that motivated her. She has committed no crime, she has merely broken a rigid and time-honored code of our society.
 Harper Lee

Quotes from the same author

When a child asks you something, answer him, for goodness’ sake. But don’t make a production of it. Children are children, but they can spot an evasion quicker than adults, and evasion simply muddles ‘em. No... you had the right answer this afternoon, but the wrong reasons. Bad language is a stage all children go through, and it dies with time when they learn they’re not attracting attention with it. Hotheadedness isn’t.
 Harper Lee
Mr. Avery said it was written on the Rosetta Stone that when children disobeyed their parents, smoked cigarettes and made war on each other, the seasons would change: Jem and I were burdened with the guilt of contributing to the aberrations of nature, thereby causing unhappiness to our neighbors and discomfort to ourselves.
 Harper Lee
The one thing that doesn't abide by majority rule is a person's conscience.
 Harper Lee
...but before I can live with other folks I've got to live with myself.
 Harper Lee
I've been writing as long as I've been able to form words. I never wrote with an idea of publishing anything until I began working on '[To Kill a] Mockingbird'. I think that what went before may have been a rather subconscious form of learning how to write, of training myself.
 Harper Lee