It seems like Harper comments on the complexity of guilt and responsibility throughout the book. Even though Sean is revealed to be the one who is actively guilty of the deaths of Gabby and Bronte, I felt that the story challenged the reader to think beyond viewing things purely in terms of personal and individual responsibility and consider how others in the community and the community as a whole could have inadvertently contributed to the deaths.
How responsible do you think the community is for what happened? What differences in factors outside of Sean do you think might have prevented the deaths regardless of what his personal inclinations and choices were under the circumstances?