The act of state doctrine is a court-made (common law) doctrine that prohibits U.S. courts from judging the validity of the official acts of a foreign country that take place within that foreign country's borders.
In South Carolina, as in other U.S. states, the act of state doctrine is recognized as a principle of federal common law rather than state statute. This doctrine suggests that U.S. courts should not examine or judge the validity of public acts performed by a recognized foreign sovereign within its own territory. The rationale behind this doctrine is to maintain respect for the sovereignty of other nations and to avoid conflicts in foreign relations that could arise from such judicial scrutiny. While the doctrine is applied at the federal level, it would also be respected by state courts in South Carolina when dealing with cases that involve foreign sovereign acts. However, the application of the act of state doctrine is subject to certain exceptions, such as when a case involves a clear violation of international law or when the U.S. government has expressed a particular interest in the matter at hand.