This is a good choice if you want to challenge your philosophy on justice and how it should be applied.

Interestingly, the whole idea of justice is twisted here: she wants the truth to come to light, yet she conveniently hides it. I feel like the point is that her actions, in the end, are justified by the fact that she uncovered a bigger secret. Still, no one gets punished. I'd argue that deciding what comes to light and what doesn't is a very dangerous position. This ultimately depends on how you view justice. Should justice apply the same way to everyone, or should it be differential depending on the culprits and victims? Most would agree that it should be the same, but practically we tend to empathize with the oppressed regardless. The flow of the movie makes me agree with her, but apart from that, I'm not so sure the chosen approach is the best in terms of truthfulness. She does say her mother already suffered the punishment, but does that truly justify her actions? I'd say it doesn't, at least not fully.
Otherwise, the movie was a pretty good one, even though it does not really have closure... I'd describe it as an open ending. While the type of story is very usual, the take on it is unexpected. Messing with truth and leaving things "unfinished" is a new approach, at least to me.