How is justice served in the final chapters of The Adventures of Huckleberry Finn?

Jim is freed from slavery at the end of the novel. The
Duke and the King are tarred and feathered and ridden out of town. Huck is also given
the news that he can return home, if he wants to, because his father is
dead. 

In various ways, these are the instances of justice
being served in the final chapters of the novel. 

The
example of Jim's freedom is the only purely positive outcome of these three, however, as
the other examples include death and punishment that offer new emotional conflicts for
Huck. 

Though Huck is not strongly affected by news of his
father's death, he is not overjoyed by the news either and he is saddened to see the two
rogues, the King and Duke, brutally punished by the
townspeople. 

The freedom that Huck has achieved in the end
has been earned though moral and physical work and so may also stand as example of
justice being served.