The 1866 Act begins with a statement from which the Citizenship Clause of the Fourteenth Amendment is derived: “[A]ll persons born in the United States, and not subject to any foreign power, excluding Indians not taxed, are hereby declared to be citizens of the United States . . .” The phrase “and not subject to any foreign power” seems clearly to exclude children of resident aliens, legal as well as illegal. The Fourteenth Amendment Citizenship Clause substituted the phrase “and subject to the jurisdiction thereof,” but there is no indication of intent to change the original meaning.
In the 39th Congress, which enacted the 1866 Civil Rights Act and proposed the Fourteenth Amendment, the question arose of how to avoid granting birthright citizenship to members of Indian tribes living on reservations. The issue was whether an explicit exclusion of Indians should be written into the Citizenship Clause as it was in the above-quoted first sentence of the 1866 Act. It was decided that this was not necessary, because, although Indians were at least partly subject to the jurisdiction of the United States, they owed allegiance to their tribes, not to the United States.
Senators Lyman Trumbull of Illinois and Jacob Howard of Ohio were the principal authors of the citizenship clauses in both the 1866 Act and the Fourteenth Amendment. Senator Trumbull stated that “subject to the jurisdiction of the United States” meant subject to its “complete” jurisdiction, which means “[n]ot owing allegiance to anybody else.” Senator Howard agreed that “jurisdiction” meant a full and complete jurisdiction, the same “in extent and quality as applies to every citizen of the United States now.” Children born to Indian parents with tribal allegiances were therefore necessarily excluded from birthright citizenship, and explicit exclusion was unnecessary. This reasoning would seem also to exclude birthright citizenship for the children of legal resident aliens and, a fortiori, of illegal aliens. It appears, therefore, that the Constitution, far from clearly compelling the grant of birthright citizenship to children of illegal aliens, is better understood as denying the grant.
Lino Graglia of the University of Texas Law School had a law review article on it a few years back: