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“Flores-Villar was born in Mexico, out of wedlock, to a United States citizen father and foreign mother. Under 8 U.S.C. §§ 1401 and 1409, United States citizen fathers of non-marital children born abroad may only transmit United States citizenship if the father had resided in the United States continuously for at least five years after age fourteen. On the other hand, United States citizen mothers with foreign-born non-marital children are only required to have one year residence in the United States to transmit citizenship. Flores-Villar challenged his Section 1325 conviction on the grounds that the differential residency requirements of 1401 and 1409 make an impermissible classification based on gender that resulted in his alien status.”
“Holding: An equally divided Court affirmed the decision of the Ninth Circuit upholding, against a constitutional challenge, a citizenship-transmission statute that imposes different standards for children born out of wedlock outside of the United States depending on whether the child’s mother or father is a U.S. citizen. (Kagan, J., recused).
Plain English Holding: By a vote of four to four (because Justice Kagan was recused), the Court allowed the lower court’s decision to stand; that decision rejected the argument that a federal law which establishes different standards for children born out of wedlock outside of the United States to obtain U.S. citizenship, depending on whether the child’s mother or father was a U.S. citizen, is unconstitutional.”
http://www.scotusblog.com/case-files/cases/flores-villar-v-united-states/
They did not base their decision on Vattel’s definition. If they had, he would have been declared a citizen of the US: “Flores-Villar was born in Mexico, out of wedlock, to a United States citizen father and foreign mother.”
The citizenship of the father would, under Vattel, automatically apply to the mother, and his birthplace would be irrelevant - under Vattel.
Being a fool plus having six cups of coffee and full of nervous energy, I went to the linky thingy and found what they were quoting in Villar whatever in a Amicus Curie brief. Which none of it made no sense anyway, and I should have known better than to even try. One of the things about helpful new citizens was by the guy who wrote Robinson Crusoe, a well known constitutional scholar of the United States.