Yes, He will ultimately judge Vitter, but that doesn't mean that we can't as well. The man is supposed to be a leader; instead he's disgraced his wife and humiliated his children. We should not tolerate people who act like this in positions of authority, or all we'll get is more of them.
My experience of being around many adulterous men in my career is that men who violate their marriage vows will violate other rules and laws, too. They come to believe that the rules simply do not apply to them, and the longer they get away with the adultery, the more it "adulterates" them and they think they can get away with anything. I worked with a few men in a previous Administration who ended up going to jail for bribery and other abuses of power, and every single one of them was also an adulterer. Bill Clinton is the ultimate example of this type of man. But David Vitter sounds to me like he is cut from the same cloth. Even worse in some ways, because as a Catholic he has committed a mortal sin by violating the sacrament of marriage.