This is a great episode for several reasons. Part of it is about how a community becomes a suspect as to how they react to these monks. Part of it is how they seem to have a greater effect then the investigation could reveal and in the end, even though the guilty party is revealed, the mmotive for the murder is plain to all who watch the episode. I thought the fact that Grissom saw a reason in the wounds and the revealed truth hits him after the fact is gold!
Catherine has her own ghosts to deal with and in the end, her choice is the right thing to do, one that we all can admire.