2241 The more prosperous nations are obliged, to the extent they are able, to welcome the foreigner in search of the security and the means of livelihood which he cannot find in his country of origin. Public authorities should see to it that the natural right is respected that places a guest under the protection of those who receive him.
Political authorities, for the sake of the common good for which they are responsible, may make the exercise of the right to immigrate subject to various juridical conditions, especially with regard to the immigrants' duties toward their country of adoption. Immigrants are obliged to respect with gratitude the material and spiritual heritage of the country that receives them, to obey its laws and to assist in carrying civic burdens.
Father Z has in a post today a Catholic World News article on Cardinal Mahoney's criticism of the Arizona bill that would require state and local law enforcement to check immigration status. I have my own thoughts on Cardinal Mahoney's stance, but regardless of one's thoughts, the article is more about His Eminence's comparison of the bill to Nazism and communism and the reaction to such a comparison.
I only glanced through the article and Father Z's personal comments. He was evenhanded in his dissection of the article. What was more interesting were the comments after the post. As of this writing, there are seventy of them, so I'm not going to attempt to sum up the different threads of argument beyond the fact that they largely focus around the interpretation of the quoted paragraph above from the Catechism. What are the rights of illegal aliens and what are the rights of citizens of the receiving country in light of the Catechism?