The United States Court of Appeals for the Fifth Circuit’s en banc decision in Nathan v. Alamo Heights Independent School District, No. 25-50695 (5th Cir. Apr. 21, 2026), does something I have been waiting on a federal appellate court to do for two years. It takes the legislative-fact versus adjudicative-fact distinction that I spotlighted at the November 2025 Federalist Society National Lawyers Convention — and that Judge Richard A. Posner laid out fourteen years ago in Moore v. Madigan, 702 F.3d 933 (7th Cir. 2012) — and uses it to slam the door on the expert-witness shakedown that anti-gun lower courts have been running on Second Amendment plaintiffs. Nathan is a First Amendment Establishment Clause case on its face. The methodology it adopts is going to do real work for the Second Amendment.
The Shakedown I Have Been Calling Out
For years now, the anti-gun side and its judicial allies have been playing a particular game. They take legal questions about the original public meaning of the Second Amendment in 1791 — questions about what James Madison wrote, what Samuel Johnson’s dictionary defined “keep and bear arms” to mean, what the founding generation understood the right to be — and they relabel them as factual questions for a trial. That relabeling triggers years of discovery, expert depositions, hired-historian battles, and seven-figure litigation bills. It is a tax on the right to keep and bear arms, and it is intentional.
Here is the distinction the trick depends on. Adjudicative facts are facts about the parties — did the defendant run the red light, did the plaintiff get denied a carry permit last Tuesday, did this particular sheriff enforce the statute against this particular gun owner. Those are jury questions. Legislative facts are facts that bear on the meaning and justification of the law itself — what does the Second Amendment mean, what did the ratifiers think it covered, what is the historical tradition of regulating arms. Those are court questions, decided by judges from briefs, treatises, and historical sources. The anti-gun playbook is to call legislative facts adjudicative, force the plaintiff into discovery, and bleed the case dry.
Posner Said It First. The Fifth Circuit Just Said It Again.
In Moore v. Madigan, Judge Posner — striking down Illinois’s flat ban on carrying ready-to-use firearms in public — addressed this directly. He wrote that the evidence at issue:
was evidence of “legislative facts” — that is, facts that bear on the justification for legislation, as distinct from facts concerning the conduct of the parties in a particular case (“adjudicative facts”).
He then drove the nail in:
Only adjudicative facts are determined in trials, and only legislative facts are relevant to the constitutionality of the challenged law.
That is the rule. Constitutionality is a legislative-fact inquiry. It is not a swearing contest between hired historians.
Now read what Judge Stuart Kyle Duncan, writing for the en banc Fifth Circuit and joined by Chief Judge Jennifer Walker Elrod, just said in Nathan. The plaintiffs there had loaded up an expert witness to argue that the Ten Commandments lacked a tradition of classroom display. The Fifth Circuit was not having it:
The Nathan plaintiffs would rely on this practice to resolve fact issues about the Ten Commandments’ role in American history. But they confuse the kind of facts experts can help determine — so-called adjudicative facts — from facts that are decided by courts — so-called legislative facts.
The opinion then cites Moore v. Madigan directly and reproduces Posner’s framing almost verbatim. The Fifth Circuit goes on:
As Judge Posner has explained, only adjudicative facts are determined in trials, and only legislative facts are relevant to the constitutionality of a challenged law.
That language, sitting in a Fifth Circuit en banc opinion covering Texas, Louisiana, and Mississippi, is now binding precedent. And the citations the Fifth Circuit drops to anchor the point are McDonald v. City of Chicago, 561 U.S. 742 (2010) (Thomas, J., concurring), District of Columbia v. Heller, 554 U.S. 570 (2008), and NYSRPA v. Bruen, 597 U.S. 1 (2022). The bridge to the Second Amendment is already in the footnotes.
The Supreme Court Has Never Played the Expert-Witness Game
Here is the part that should end the argument. Count the testifying historian-experts on the meaning of the Second Amendment used by the Supreme Court of the United States in Heller (2008): zero. In McDonald (2010): zero. In Caetano v. Massachusetts, 577 U.S. 411 (2016): zero. In Bruen (2022): zero. In United States v. Rahimi, 602 U.S. 680 (2024): zero. In Wolford v. Lopez, No. 24-1046, argued before the Court on January 20, 2026: zero. In United States v. Hemani, No. 24-1234, argued March 2, 2026: zero.
The Supreme Court has decided every major Second Amendment case of the modern era on briefs, treatises, founding-era statutes, and historical research — never on a trial transcript of expert testimony. Caetano is the cleanest illustration. Justice Samuel A. Alito Jr., joined by Justice Clarence Thomas, concurred in the judgment and treated the common-use of stun guns as a legislative fact. He did not call witnesses. He cited a law review article — Eugene Volokh’s piece in 62 Stan. L. Rev. 199 (2009) — and a Michigan Court of Appeals decision, and he relied on published civilian-ownership numbers. Secondary sources. Treatises. Court records. That is how legislative facts work.
What This Means for Our Side
The strategic implication is straightforward. Groups carrying the load in this litigation — the Second Amendment Foundation, the Firearms Policy Coalition, the NRA, the Gun Owners of America, the California Rifle and Pistol Association — should never again concede that the original public meaning of the Second Amendment is a jury question or a battle-of-the-experts question. When a district court orders Second Amendment plaintiffs into expert discovery on founding-era history, that order is now in direct tension with binding Fifth Circuit precedent and with how the Supreme Court itself has done business from Heller through Hemani. Cite Nathan. Cite Moore. Cite Posner by name. Refuse the shakedown.
I have been arguing for years that the anti-gun movement’s structural advantage is not in the law — it is in the budget, the calendar, and the credentialed-expert industry the universities feed it. Strip out the expert-witness apparatus and you strip out the advantage. The Fifth Circuit just handed us the tool to do that.
This article is based on analysis by Professor Mark W. Smith, constitutional attorney and Host of the Four Boxes Diner 2nd Amendment channel. Watch the original video here. This does not constitute legal advice.