Daisy Miller is an independent character that chooses to ignore the social customs that limit her. In a sense, she is ignorant to the ways in which established society expects her to behave. Daisy becomes representative of a lamb eaten alive by a pack of wolves. She is inherently an innocent characater that dares to stray off the path, not fully understanding that she is straying off the path.
While Daisy never actually does anything bad, she behaves in a way that leads the people around her to immediately judge the way she appears. Daisy does things that are not acceptable by society's standards, such as going off alone with a male, and immediately becomes the subject of gossip which is fueled by more gossip.
Daisy becomes the victim of society's oppression of those who will not conform to accepted standards. This happens to her not because she is actually a bad person, but because she is an innocent girl that happens to be unconventional.