The citizenship clause of the 14th Amendment states that "all persons born or naturalized in the United States and subject to the jurisdiction thereof" are citizens. Some legal scholars argue that this clause does not extend citizenship to children born in the U.S. to illegal or temporary residents. Professor John Yoo has published an op-ed asserting that a limited interpretation of this clause disregards historical evidence and established judicial practices.

Supporters of birthright citizenship often reference the common-law rule established by 18th-century English jurist William Blackstone, but they frequently overlook the views of American jurist Joseph Story, who suggested that children of aliens temporarily present in the U.S. should not automatically receive citizenship. Additionally, the Civil Rights Act of 1866, which laid the groundwork for the 14th Amendment, defined citizenship in a manner that excluded children of parents who owed allegiance to foreign powers.

Senator Lyman Trumbull, a key author of the citizenship clause, indicated that the language was intentionally crafted to exclude U.S.-born children of parents with temporary status. This historical context is often omitted in contemporary discussions.

The 14th Amendment's language differs from that of the Civil Rights Act, but legislative history suggests that the amendment was designed to clarify citizenship for Native Americans, who were not considered citizens until the Indian Citizenship Act of 1924. The Supreme Court's ruling in Elk v. Wilkins highlighted that Native Americans owed allegiance to their tribal governments rather than the U.S.

Moreover, early executive branch decisions have denied citizenship claims for U.S.-born children based on their parents' immigration status, indicating a historical precedent for limiting birthright citizenship. The Slaughter-House cases of 1873 further clarified that the citizenship clause was intended to exclude children of foreign diplomats and consuls.

The ongoing debate over the interpretation of the citizenship clause raises significant questions about the implications for social equity and the treatment of individuals born in the U.S. to non-citizen parents, reflecting broader issues of immigration policy and human rights.