Abstract
The Citizenship Clause of the Fourteenth Amendment confers birthright citizenship in cases of lawfully domiciled aliens, but not in cases of illegal immigration or legal visitation by aliens. The best reading of the original understanding in the 1860s is that the Clause impliedly requires parental domicile in the United States, domicile in turn requires some degree of allegiance, but parents who have not been received into the U.S. cannot pay any allegiance, so these requirements can only be reconciled by domicile de jure — that is, the domicile must be legal. This dichotomy between de jure and de facto domicile was well-known in the 1860s. In cases of illegal immigration, citizenship for U.S.-born children should be sought via naturalization, and the same in cases of legal visits by temporary foreign visitors. Intertwined with birthright citizenship is the Clause’s guarantee of state citizenship, and scholars who say that Washington D.C. is out of compliance are correct, because the federal government has failed to ensure state citizenship there.