There are different ways one can approach justice in haven. If justice means the enforcement of law, we can say it's universal because the hearthlaw is also universal. All players share the same set of rules, basically ensuring that life and private property are their unalienable rights. I'm able to steal stuff and kill people, but doing so is against those rights, which is why scents and nidbanes exist.
But if justice is understood as conceptions of what's morally right and wrong, then of course it will vary. What the OP seems to be studying is how different conceptions of justice coexist in an originally anarchic society. What I think he is asking for here are examples of how different forms of justice have been enforced by different factions in haven history.
I'd guess stories of rangers, world police, executions, faction neutrality etc would make good examples in this context.