JUSTICE BRETT KAVANAUGH’S TEASE: THE ILLUSION OF STATUTORY SUFFICIENCY
Justice Kavanaugh's Concurrence in Trump v. Barbara and the Structural Limits of Legislative Power Over the Citizenship Clause
By: Professor Gilbert N.M.O. Morris
Nassau, N.P., The Bahamas
Constitutional Jurisprudence Series
Abstract
This article examines the concurrence of Justice Brett Kavanaugh in Trump v. Barbara (2026), decided by the Supreme Court of the United States on June 30, 2026, and the popular misreading of that concurrence as a legislative shortcut around the Fourteenth Amendment's Citizenship Clause.(1) The prevailing account, circulated widely in political commentary following the decision, holds that Congress may now, by ordinary statute, narrow birthright citizenship without recourse to Article V. This article argues that such an account confuses three distinct constitutional operations, that Justice Kavanaugh's own language forecloses the reading given it, and that the arithmetic of the Court's five-justice constitutional majority renders any statute of the kind proposed presently unsustainable.
I. Axiom
A constitutional command operates as the ground upon which all statutes stands. It is not one enactment among the many that Congress may set beside it, but the condition of their validity. Where a statute contradicts a constitutional norm, the statute is void from its inception to the extent of the contradiction and its logical linguistic entrails, and no legislative majority, however durable, converts an ultra vires enactment into law by the mere act of passing it.
This axiom is not original to the present inquiry. It is the axiom of Marbury v. Madison (1803), and it governs every subordinate question that follows.(2)
II. Definition
Three operations must be held apart, since the commentary surrounding Trump v. Barbara collapses them into a single undifferentiated act of "legislating on citizenship.
The first is the amending of a constitutional norm, reserved by Article V to two-thirds of both Houses of Congress and three-quarters of the states.
The second is the judicial construction of a norm's scope, which the Constitution commits to the courts alone (per Marbury aforementioned), and which the Supreme Court exercised in both the majority and the dissenting opinions of Trump v. Barbara.
The third is legislative implementation of a norm's non-self-executing particulars, exemplified by the citizenship statute Congress first codified in 1940 and carried into the Immigration and Nationality Act of 1952, presently codified at 8 U.S.C. - 1401(a), which gives procedural body to a substantive guarantee already complete in the constitutional text.(3) The distinction between the second and third operations is the axis on which the entire controversy turns, for a statute enacted under the third power remains at all times subject to testing under the second.
III. Proposition
The proposition advanced by the circulated commentary is that Justice Kavanaugh's concurrence supplies Congress with authority, exercised through ordinary statute, to establish exceptions to birthright citizenship for children of parents unlawfully or temporarily present, and that this authority requires no constitutional amendment. This article's counter-proposition is narrower and, I submit, more faithful to the opinion itself.
Justice Kavanaugh reasoned that the executive order failed under 1401(a) rather than under the Fourteenth Amendment, and stated that Congress could amend the statute or enact new legislation establishing such exceptions.(4) The qualifying condition attached to that proposal is decisive. The new legislation, in his own formulation, must remain consistent with the Fourteenth Amendment.(4)
Whilst I have my own questions concerning Justice Kavanaugh’s jurisprudence, the opinion does not propose that ordinary statute may contradict the Amendment. It proposes that the Amendment's own historical exceptions, the four exceptions recognized in United States v. Wong Kim Ark (1898), ought not be treated as fixed at 1868, since treating them as a closed set is, in his words, inconsistent with the Court's longstanding approach to constitutional interpretation.(5)
A statute drafted on this theory does not override the Amendment. It attempts to occupy a category the Amendment, properly construed, is argued already to contain.
IV. Proof
The distinction bears immediately upon the arithmetic invoked by proponents of the legislative-shortcut reading. The vote in Trump v. Barbara was six to three as to invalidating the executive order, and five to four as to the constitutional ground for doing so.(6) The five justices sustaining the constitutional holding, Chief Justice Roberts writing for Justices Kagan, Sotomayor, Barrett, and Jackson, form a majority against any exception-expanding theory whatsoever. Justice Jackson wrote separately for the express purpose of rejecting a race-limited construction of the Fourteenth Amendment, arguing that the Reconstruction Amendments function as a civilisational reset rather than a race-specific remedy.(7)
Justice Kavanaugh's opinion, by contrast, stands alone in its structure, concurring in the judgment while dissenting from the constitutional reasoning.(8) Justice Thomas, joined in part by Justice Gorsuch, argued a domicile theory holding that the Fourteenth Amendment extends citizenship only to those permanently domiciled within the United States, a broader and structurally distinct claim from Justice Kavanaugh's narrower test of exceptions relevantly similar to those already recognized.(9) A future statute seeking constitutional sanction under Justice Kavanaugh's theory would therefore require the reconciliation of two dissenting positions that do not share a common doctrinal logic, and would require, further, the conversion of a single justice's concurrence into a majority holding, since a concurrence in judgment establishes no precedent binding a later panel.
V. Argument
What is noteworthy is the commentary under review - accusing Kavanaugh of holding a latch door open - performs the conflation the definitional section above was constructed to prevent. It treats a single justice's hypothesis about a future controversy, a hypothesis contingent on litigation not yet filed and votes not yet secured, as an operative grant of legislative authority already completed. This is a recognisable pattern in political rhetoric under conditions of urgency, wherein contingency is narrated in the grammar of accomplishment. The declarative structure of the Citizenship Clause itself supplies the answer the commentary elides. Chief Justice Roberts, writing for the majority, found no textual or historical warrant for reading a domicile limitation into the Clause's declarative grammar, observing that the Court's exhaustive review of the Clause's text and history identified no evidence that its ratifiers intended such a limitation.(10) Justice Kavanaugh did not dispute this reading of the Clause's declarative force. His disagreement is confined entirely to the closed-set question, a narrower terrain that leaves the sentence, ‘all persons born are citizens’, untouched as a governing rule, and contested only as to the outer boundary of its historical exceptions.
VI. Corollary
It follows that the phrase circulating in political commentary, that no constitutional amendment is necessary, is true only within the bounds of Justice Kavanaugh's own unadopted theory, and that theory has not commanded a Court. It follows further that any statute enacted on the strength of this theory would arrive before the judiciary as an open constitutional question rather than as settled legislative territory, and would face, at minimum, the five-justice constitutional majority already on record against exception-expansion, together with the structural incompatibility between Justice Kavanaugh's relevantly-similar test and Justice Thomas' domicile theory, which cannot be harmonized into a single five-vote coalition without one side abandoning its own reasoning; a fear which seems to lie at the feet of Chief Justice Roberts…who has built a reputation of incongruent rulings, coming into coherence only after some unthinkable justice mischief has been done…such as gutting the Voting Rights Act or ceding disfiguring immunities to the Executive.
VII. Measured Restatement
Congress retains no power, under any opinion issued in Trump v. Barbara, to enact a statute directly contradicting the Fourteenth Amendment's guarantee of citizenship to persons born within the jurisdiction of the United States. What Justice Kavanaugh's concurrence opens is a narrower and considerably more precarious avenue: legislation framed as an extension of the Wong Kim Ark exceptions, sustainable only if a future Court, differently constituted in its reasoning from the present one, adopts his characterisation of those exceptions as an open rather than closed category.
This is a wager upon future adjudication. It is not a completed transfer of constitutional authority to the legislature.
VIII. Conclusion
Justice Kavanaugh's concurrence supplies a fourth analytical strand for the constitutional jurisprudence of Trump v. Barbara, distinct from Justice Thomas's domicile theory and Justice Jackson's genealogical method, and it exhibits, in miniature, the pattern this author has identified elsewhere in Chief Justice Roberts's jurisprudence this term: formal resolution of the judgment before the parties, joined to an unresolved structural lacuna, here the undefined boundary of the phrase relevantly similar, left open for future litigation to fill. The lacuna is not a defect of careless draftsmanship. It is the characteristic form by which this Roberts Court, term after term, resolves the case before it whilst declining to resolve the doctrine beneath it, a form worth naming; since a jurisprudence built upon the studied deferral of its own foundational questions is a jurisprudence that governs the present at the cost of cogency in the present and the coherence of the it’s constitutional future.
References
1. Trump v. Barbara, No. 25A-___ (U.S. June 30, 2026) (slip op.), as reported in "Trump v. Barbara," https://en.wikipedia.org/wiki/Trump_v._Barbara (accessed July 3, 2026)
2. Marbury v. Madison, 5 U.S. (1 Cranch) 137 (1803).
3. 8 U.S.C. § 1401(a); Immigration and Nationality Act of 1952, Pub. L. No. 82-414, 66 Stat. 163; Nationality Act of 1940, Pub. L. No. 76-853, 54 Stat. 1137.
4. Scott Bomboy, "Supreme Court Strikes Down Trump's Birthright Citizenship Executive Order in Landmark Decision," National Constitution Center (June 2026), https://constitutioncenter.org/blog/supreme-court-strikes-down-trumps-birthright-citizenship-executive-order-in-landmark-decision
5. "The Alarming Split in the Supreme Court's Birthright Citizenship Ruling," Salon (July 2, 2026), https://www.salon.com/2026/07/02/the-alarming-split-in-the-supreme-courts-birthright-citizenship-ruling/.
6. "Trump v. Barbara," supra note 1.
7. "Supreme Court Reaffirms Birthright Citizenship Under the 14th Amendment in Trump v. Barbara," FindLaw (June/July 2026), https://www.findlaw.com/legalblogs/supreme-court/supreme-court-reaffirms-birthright-citizenship-under-the-14th-amendment-in-trump-v-barbara/.
8. "Trump v. Barbara," supra note 1; SCOTUSblog, "Breaking Down the Birthright-Citizenship Decision" (2026), https://www.scotusblog.com/2026/06/breaking-down-the-birthright-citizenship-decision/.
9. FindLaw, supra note 7.
10.National Constitution Center-supranote 4
11.National Constitution Center, supra note 4 (reporting the decision's length at 194 pages).
Source / Comment
