Absent a legal framework you cannot have justice kinda by definition.
Strong disagree! I judge legal frameworks against my preexisting conception of justice. I don’t decide something is just or unjust merely because a legal framework judges it one way or another. (Though my own judgment may take into account “there is a legal framework in play here which says...”)

No, I agree justice and morality are different. But like, if a legal system says “if you smoke pot you get life in jail”, I say “that is not just, this legal system does not even seem to be trying for justice” rather than “I guess that’s just, even though it’s deeply immoral”.