Catechism of the Catholic Church §2499 — excerpt
Moral judgment must condemn the plague of totalitarian states which systematically falsify the truth, exercise political control of opinion through the media, manipulate defendants and witnesses at public trials, and imagine that they secure their tyranny by strangling and repressing everything they consider "thought crimes."
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.