There's controversy concerning whether the opening language of the 14th Amendment actually establishes birthright citizenship. Here's the text:
All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside.
The highlighted text appears to be the tricky part. Are illegal immigrants truly subject to the jurisdiction of the United States? Can they vote and are they subject to a draft, if one were established? The courts have never ruled on this issue -- it took a court ruling to determine that the children of legal immigrants were citizens -- so we simply don't know.
- CRS Report: U.S. Citizenship of Persons Born in the United States to Alien Parents.
- Christian Science Monitor: Is Birthright Citizenship Really in the Constitution?
- Wikipedia: Birthright Citizenship in the United States.
- Wikipedia: Jus Soli.
- Wikipedia: Jus Sanguinis.
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