The 14th Amendment — ratified after the Civil War and ensuring that former slaves were U.S. citizens — provides that “[a]ll 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 plaintiffs focus on the first part, but barely glance at the second, arguing that, with few exceptions (such as the children of foreign diplomats in the United States), anyone born in the United States is “subject to its jurisdiction,” simply by virtue of being within its borders.

They do this by relying almost entirely on United States v. Wong Kim Ark, an 1898 U.S. Supreme Court opinion that the plaintiffs get hopelessly wrong. In Wong, the court held that a man born in San Francisco to Chinese immigrants was a U.S. citizen under the 14th Amendment. Omitting some key facts, the plaintiffs argue this means that all children born in the United States of all immigrant parents, with the aforementioned very rare exceptions, automatically are U.S. citizens. Even a cursory read of the opinion, however, shows that the Supreme Court ruled nothing of the sort.

SCOTUS sided with Wong, but for a very important reason the plaintiffs fail to mention: Wong’s parents were legal immigrants to the United States. The entire foundation of the plaintiffs’ argument — that SCOTUS has already upheld birthright citizenship for the children of illegal immigrants by this decision — is therefore completely and obviously wrong.