50 It is obvious that no thought is being taken of the spiritual good of the faithful if the Church's laws are being violated, and further, there is no question of vacant sees, as they wish to argue in defense, but of episcopal sees whose legitimate rulers have been driven out or now languish in prison or are being obstructed in various ways from the free exercise of their power of jurisdiction. It must likewise be added that those clerics have been cast into prison, exiled, or removed by other means, whom the lawful ecclesiastical superiors had designated in accordance with canon law and the special powers received from the Apostolic See to act in their place in the government of the dioceses.
Source: Ad Apostolorum Principis (Vatican.va)