The USCIS will normally presume a foreign marriage is valid based on presentation of an official certified marriage certificate. As a general rule, the validity of a marriage is judged by the law of the place of where the marriage occurred.
If the marriage is voidable but no court action to void the marriage has taken place, it will be considered valid for immigration purposes. However, if a marriage is valid in the country where celebrated but considered offensive to public policy of the United States, it will not be recognized as valid for immigration purposes. Plural (i.e. polygamous) marriages are examples of marriages that may be valid under foreign law but are not recognized as valid for U.S. immigration purposes.
The underlying principle in determining the validity of the marriage is that the law of the place of marriage celebration controls (except as otherwise noted below). If the marriage was properly and legally performed in the place of celebration and legally recognized, then the marriage is deemed to be valid for visa adjudication purposes. Any prior marriage, of either party, must be legally terminated before the later marriage.
Certain marriages that are legal in the place of celebration, but are void under state law as contrary to public policy, are not valid for visa adjudication purposes. Polygamous marriages are not recognized as a matter of federal public policy. Any prior marriage, of either party, must be legally terminated before the later marriage. Certain marriages between relatives may be void because of public policy concerns even if the place of celebration recognizes the marriage. A marriage void under state law, such as a relative marriage, may nevertheless be recognized as valid by the state of intended immigration. The legal thresholds vary state by state. For example, first cousins may not marry in Michigan and such marriages in Michigan are considered void from their inception (M.C.L.A. 551.3 (2010)). A 1973 ruling of the Michigan Supreme Court, however, found a marriage between first-degree cousins married in Hungary was nevertheless valid. See Toth v. Toth, 50 Mich. App 150, 212 N.W.2d 812 (1973).
Certain underage marriages involving an individual under the age of 18 may be void because of public policy concerns even if the place of celebration recognizes the marriage as valid. Legal thresholds for underage marriage vary state by state. Some states may recognize a marriage performed in another jurisdiction even if state law would not allow the parties to enter into a marriage in that state, while other states would not recognize such a marriage because it violates the public policy of the state.