Why the Birthright Citizenship Case Matters—Even for Vaccine Lawyers

By - Joe Zamboni, J.D., M.P.H.

So this isn’t vaccine law - but it’s a Supreme Court case I’m watching closely.

In the coming days, the Court is expected to issue its decision in the birthright citizenship case challenging President Trump’s executive order limiting automatic citizenship for certain children born in the United States. It is likely the highest-profile case still awaiting a decision this Term.

At its core, the case asks whether the Fourteenth Amendment’s Citizenship Clause guarantees birthright citizenship as it has long been understood under United States v. Wong Kim Ark (1898), or whether the Constitution permits a narrower interpretation. Most constitutional scholars view the administration’s argument as an uphill battle, but this Supreme Court has shown a willingness to revisit long-settled legal questions.

Why does that matter to those of us who follow vaccine law?

Because vaccine jurisprudence also rests on longstanding precedent - most notably Jacobson v. Massachusetts (1905), which has shaped public health law for more than a century. The legal issues are entirely different, but the institutional question is similar: How willing is this Court to reconsider foundational precedents?

If the Court were to significantly reinterpret the Fourteenth Amendment or narrow the reach of Wong Kim Ark, it would reinforce the idea that even century-old decisions are not necessarily beyond reconsideration. That does not mean Jacobson is next, nor would such a ruling directly affect vaccine law. But it would provide another data point about the Court’s approach to precedent and its willingness to revisit constitutional doctrines that many once considered settled.

We’ll know more soon. Regardless of the outcome, it’s a decision worth watching—not just for immigration law, but for anyone interested in where the Supreme Court may be headed.