6 Lastly, the baseness of dueling is so evident, that in our time, despite theapproval and patronage of many, legislators have felt bound to repress it bypublic authority and published penalties. What is so perverse and destructive inthis case is that the written laws for the most part are evaded in substance andin deed; and this often happens with the knowledge and silence of those whoseduty it is to punish the guilty and see to it that the laws are enforced. Thusit happens that frequently duels are fought and go unpunished, mocking the law.
Source: Pastoralis Officii (Vatican.va)