I don't think they mean it to go quite that high. Sounds like they're trying to prevent bishops and archbishops from doing cover-ups.
From what I think I understand (from long ago reading Richard Cavendish's History of Magic), the RC Church's best intention is to save as many people's souls as possible, for which they need lots of priests out in the field delivering RC rites to people, because apparently your soul can't be saved unless you receive Holy Communion and whatnot. And there's Church law that Communion etc. are valid even if the priest who administers them is in a state of sin. So the Church has a strong motive to cover up misconduct by priests in order to keep those priests in the field where they can save more souls. Ironic? It gets better. The reason (I've heard and do in part believe) the Church has this rule, is that in the early centuries of the RC Church, they had a problem with congregations covering up the misconduct of their priests, out of a perception that if the priest was found to be in a state of sin, then the rites administered by that priest would be invalidated and suddenly everyone in the congregation would be damned to Hell. So the Church, in order to prevent congregations from covering up for their priests, proclaimed the rites are valid even if the priest conducting them is in a state of sin.