There are varying interpretations of the original intent of Congress, based on statements made during the congressional debate over the amendment. During the original debate over the amendment Senator Jacob M. Howard of Michigan—the author of the Citizenship Clause—described the clause as having the same content, despite different wording, as the earlier Civil Rights Act of 1866, namely, that it excludes Native Americans who maintain their tribal ties and "persons born in the United States who are foreigners, aliens, who belong to the families of ambassadors or foreign ministers." According to historian Glenn W. LaFantasie of Western Kentucky University, "A good number of his fellow senators supported his view of the citizenship clause." Others also agreed that the children of ambassadors and foreign ministers were to be excluded. However, concerning children born in the United States to parents who are not U.S. citizens (and not foreign diplomats), three Senators, including Senate Judiciary Committee Chairman Lyman Trumbull, the author of the Civil Rights Act, as well as President Andrew Johnson, asserted that both the Civil Rights Act and the Fourteenth Amendment would confer citizenship on them at birth, and no Senator offered a contrary opinion.
Senator James Rood Doolittle of Wisconsin asserted that all Native Americans were subject to the jurisdiction of the United States, so that the phrase "Indians not taxed" would be preferable, but Trumbull and Howard disputed this, arguing that the U.S. government did not have full jurisdiction over Native American tribes, which govern themselves and make treaties with the United States.
In Elk v. Wilkins, 112 U.S. 94 (1884), the clause's meaning was tested regarding whether birth in the United States automatically extended national citizenship. The Supreme Court held that Native Americans who voluntarily quit their tribes did not automatically gain national citizenship.
The clause's meaning was tested again in the case of United States v. Wong Kim Ark 169 U.S. 649 (1898). The Supreme Court held that under the Fourteenth Amendment a man born within the United States to Chinese citizens who have a permanent domicile and residence in the United States and are carrying on business in the United States—and whose parents were not employed in a diplomatic or other official capacity by a foreign power—was a citizen of the United States. Subsequent decisions have applied the principle to the children of foreign nationals of non-Chinese descent.