Which character in The Scarlet Letter is innocent?

A case could be made for more than one character, but the purest is Pearl. She didn't choose the situation into which she was born. Instead, she was outcast for someone else's actions (or rather, several other people's actions), and grew up more like a natural creature than a socialized one. She's not without violent tendencies, but even these seem like natural desires, rather than sin or corruption.