When fellow Villanova alumnus Pope Leo XIV was selected as the first American to assume the Vatican's highest office, the U.S. tax system was faced with an issue it had yet to encounter: a U.S. citizen who is also a foreign sovereign. There have been various suggestions about how to account for this unprecedented event. Some propose that the pope should renounce his citizenship, while others believe the U.S. should create an exception.

Robert Goulder: Well, absolutely, and that comes up in all the literature that's out there swirling around this issue. Sovereign immunity, what I'm going to talk about later, is one of the three ways out of this crisis, but let's talk about what it is. There is a legal doctrine that foreign heads of state or heads of government should not be subject to the laws of another jurisdiction, and that is actually rooted in international law. There's something called the 1961 Vienna Convention of Diplomatic Affairs, and there's an authority there for multiple different varieties of sovereign immunity.