What Is Birthright Citizenship, Anyway? An Explainer

Donald Trump exits the Manhattan Supreme Court following service of jury duty on Monday. Trump's proposal to revoke birthright would go against several precedents in constitutional law. Brendan McDermid/REUTERS

Birthright. If you were born in the United States, you have it. Everyone is now learning what it is, thanks to the GOP's leading presidential candidate, Donald Trump.

The Donald made a splash on Fox News Channel's The O'Reilly Factor Tuesday night with some (more) controversial comments. This time, Trump wasn't targeting Hillary Clinton, Megyn Kelly, "rapists, murderers, criminals," or Jeb Bush. He went after a different foe, one that could make it difficult for him to enact his immigration policies as president: the United States Constitution.

The background: On Sunday, Trump's campaign released a policy paper on immigration. The paper promises the "mandatory return [deportation] of all criminal aliens" and vows to "end birthright citizenship." Birthright citizenship, which Trump referred to on the Factor by using the phrase "anchor babies," is a legal precedent stating that persons born in the United States have the rights and protections of citizens.

The 14th Amendment to the Constitution, which is the basis of birthright and was passed in 1868, states, "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 amendment, part of Reconstruction after the Civil War, granted the rights of citizenship to former slaves. It also contains language about equal protection of rights for all citizens, which played a key role in the landmark Brown v. Board of Education Supreme Court ruling on segregated public schools in 1954.

Supporters of Trump's views will point to the phrase "subject to the jurisdiction thereof" to argue that people born of undocumented parents do not necessarily qualify for citizenship. They illustrate their cause by referring to 1884, when the Supreme Court ruled that children born into Native American tribes were not citizens. That decision was rendered moot when Congress extended citizenship to all Native Americans in 1924 with the Indian Citizenship Act, which opponents of birthright citizenship cite as evidence that Congress can amend the definition of citizenship

But, in 1982, the court ruled in Plyler v. Doe that the "jurisdiction" clause could not be used as the basis for denying admittance of "illegal alien" children to public schools. The ruling said, "Use of the phrase 'within its jurisdiction' confirms the understanding that the Fourteenth Amendment's protection extends to anyone, citizen or stranger, who is subject to the laws of a State, and reaches into every corner of a State's territory."

Worse for Trump, in 1898, the Supreme Court ruled in United States v. Wong Kim Ark that children born in the United States to noncitizen parents are still United States citizens, under the amendment.

That could be problematic for any candidate advocating mass deportation of "anchor babies." According to Trump's policy paper, the justification for ending birthright would be the following:

This remains the biggest magnet for illegal immigration. By a 2:1 margin, voters say it's the wrong policy, including Harry Reid who said "no sane country" would give automatic citizenship to the children of illegal immigrants.

Wrong policy or not, birthright citizenship is almost certain to withstand judicial challenge, which is something that O'Reilly recognized. "Now, there is a way to do it," the broadcaster said. "And that is to try to get the Constitution amended. Do you know how to do that?"

"I'd rather find out whether 'anchor babies' are actually citizens," Trump replied, adding that he was planning on "testing" this later in his campaign. He told O'Reilly that legal associates were planning on filing a federal suit to determine the legality of birthright.

Trump went on to say that he knows of "many lawyers" and some "very, very good lawyers," who have argued that the Constitution does not protect the rights of babies born to immigrant parents without legal status.

Trump also said that massive deportations are only part of his solution. "We need to start by building a wall," he said. "A big, beautiful, powerful wall."

The Constitution is its own sort of wall, one that could frustrate a President Trump.

Trump told O'Reilly that his reasons for advocating deportation include "taking back jobs" and a "literal crime rave," by which he meant "a literal crime wave."