Libation Bearers Theme of Fate and Free Will

This being a Greek tragedy and all, there is lots of ambiguity about the question of whether individuals have free will, or whether they are just controlled by fate. Just as in Agamemnon, Part 1 of the Oresteia trilogy, problems of fate and free will are closely linked with the overarching themes of revenge and justice in Libation Bearers. On the most basic level (not that it's very basic), these themes are connected because the idea of fate seems to give the idea of justice a hard time. After all, if people are fated to commit crimes, how can it be just to punish them?

1. Does Libation Bearers portray fate and free will as complete opposites, or is there some wiggle-room between the two ideas?
2. If Orestes does what he does partly in order to prove Apollo's oracle right, does that mean that the oracle doesn't really have the power to predict the future? What difference do you think it would make if Orestes had never heard of the oracle?
3. Libation Bearers shows that free will isn't only limited by the gods; it can also be limited by human means, as when one group of people (the Chorus) is enslaved by another (the rulers of Argos). Which of these constraints on free will is most difficult? Does being enslaved deprive the Chorus women of all agency?
4. At several points in the play, Orestes acts as if it doesn't matter whether we have Free Will or not? Why does he think this, and how might this belief influence his actions?

Based on what we see happen in Libation Bearers, it is impossible to tell whether free will exists or not.

In the world of Libation Bearers, free will is irrelevant; those who commit crimes must be punished, whether or not they intend to commit them.