For the past several decades, originalism has been the preeminent conservative legal philosophy. The basic idea of originalism—that statutes and constitutional provisions should be given their literal, original meaning—is simple and straightforward. As a consequence, originalism often takes the blame for unpopular decisions by the ultraconservative Supreme Court majority. For instance, after the Court repealed Roe v. Wade and deprived millions of women of the opportunity to receive safe abortions, the Brennan Center, a liberal think tank, lamented that originalism poses “a threat to modern life.”

But originalism’s luster in the conservative legal movement seems to be fading—and something much worse threatens to take its place. The first critical moment in this trend followed the Court’s decision in Bostock v. Clayton County, which used the text-centric principles of originalism to find that the Civil Rights Act protects gay and transgender people. The reaction on the right was predictably hysterical. John Horvat, a conservative academic, wrote a polemic against Bostock, arguing that originalism is a product of “the moral decadence of the times” and that we must instead return to “natural law, written on the hearts of men, valid for all peoples and places, providing the foundation of moral certainty.”

If you haven’t been keeping up with developments in the conservative legal movement, the term “natural law” might not ring a bell. Until pretty recently, natural law was the ugly stepchild of the conservative legal movement, always standing in the shadow of its more illustrious sibling, originalism. But as skepticism of originalism grows, natural law is gaining immense traction among conservative jurists and legal scholars.

On the current Supreme Court, Clarence Thomas, Neil Gorsuch, and Amy Coney Barrett are closely associated with natural law. In a speech in the 1980s, Thomas proclaimed that “the American Constitution [is] unintelligible without the Declaration of Independence, and the declaration is unintelligible without the notion of a higher law by which we fallible men and women can take our bearings.” Barrett, a conservative Catholic “steeped in natural-law teachings,” wrote in 1998 that Catholic judges should recuse themselves from cases where their religious beliefs might conflict with their judicial duties—because, in her words, “a judge who is heedful of ecclesiastical pronouncements cannot dispense” impartial justice. More telling than this statement itself is Barrett’s blatant refusal to follow it—she hasn’t recused herself from death penalty or abortion cases, despite the Church’s “ecclesiastical pronouncements” on those issues.¹ Gorsuch completed his doctoral thesis under the supervision of John Finnis, the foremost living exponent of natural law (more on him later), and later wrote a book arguing that legalizing physician-assisted suicide was contrary to natural law.

These justices are just part of a larger trend. A legion of conservative lower court judges and legal academics have begun to express interest in resurrecting natural law. The spread of natural law in the upper echelons of our legal system should scare people. It’s a radical and extreme philosophy, and its rise portends sinister changes to American law.

The Meaning of Law

Understanding natural law theory and why it’s so radical requires a quick foray into different ways of thinking about what “law” is. Most modern theories of law fall into a school of thought called “legal positivism,” which assumes that “law” is the will of a sovereign as enacted through established procedures. In republics like the United States, the people are the sovereign, and they express their will through representative institutions like Congress. In an absolutist monarchy, the monarch is the sovereign, and his or her commands are the law. Thus, for a legal positivist, law is simply the set of human-made rules that govern society.

Natural law comes from a fundamentally different intellectual tradition. The basic idea of natural law is that by studying human nature and the conditions of the world, and by consulting one’s own instincts, one can discover intrinsically true moral principles—and that these principles form the basis for all valid laws. Law, in other words, is immanent in nature (hence the name “natural law”), not man-made.

The ur-text of natural law jurisprudence is the Treatise on Law, written in the 1200s by Catholic saint and philosopher Thomas Aquinas. Aquinas argued that through experience, people gain insight into human nature, and from human nature, people can derive intrinsically true moral principles. For instance, through my experience, I know most people would rather live than die, so I can infer that a desire to live is part of human nature. From those premises, I can conclude that one person killing another violates the natural order of things, leading to the principle, “one must not kill.”

How do these principles relate to positive—that is, human-made—law? Aquinas explained that positive laws are valid only to the extent that they comport with natural law. “[E]very human law,” he wrote, “has just so much of the nature of law, as it is derived from the law of nature. But if at any point it deflects from the law of nature, it is no longer a law but a perversion of law.” 

That reasoning might seem plausible (and appealing) when applied to murder. But Aquinas, like other natural law theorists, didn’t stop there. By his logic, all “unnatural” acts by definition contravene the law of nature—and therefore warrant state prohibition. For example, here’s his take on why heterosexual sex is fine, but homosexual sex isn’t:

By human nature we may mean either that which is proper to man … or we may mean that nature which is common to man and other animals; and in this sense, certain special sins are said to be against nature; thus contrary to sexual intercourse, which is natural to all animals, is unisexual lust, which has received the special name of the unnatural crime (emphasis mine).²

In other words, “unisexual lust” is “unnatural”—and therefore it is a crime. And, by Aquinas’ logic, because homosexual sex violates natural law, any positive law that permits such conduct is “no longer a law but a perversion of law.”

That is the core problem with natural law philosophy. It starts by identifying moral tenets that are supposedly immanent in nature (usually based on theology, because what’s more natural than God’s will?) and claims that those tenets reflect “natural law.” Then, it says positive laws are valid only insofar as they reflect the natural law. Natural law theory is, in short, a justification for using the state to enforce the natural law theorist’s moral convictions. If you think that sounds like a recipe for authoritarian theocracy, you are correct.

The Greater of Two Evils

Natural law makes originalism look warm and cuddly by comparison. At least originalism falls in the positivist camp. For an originalist, the government makes law by setting out a collection of words that define rules people must follow. Therefore, to discern what the law means, judges should focus on the words that make up its text. To quote Justice Scalia, the man who put originalism front and center of the conservative legal movement, “[t]he text is the law, and it is the text that must be observed.”³

To be clear, originalism is still a bad legal philosophy. Determining the “original” meaning of words is a perilously subjective exercise, and originalist judges usually settle on meanings that reflect their own political views. Query why the Second Amendment protects assault rifles, which didn’t exist when the Constitution was drafted. And even when it’s possible to discern the original meaning of old words, that meaning is often profoundly undemocratic—after all, the framers of the Constitution owned slaves and thought only white male property owners should vote.

But, critically, originalism has an inherent and logical limit: the text of the Constitution and duly enacted statutes. While an originalist might hesitate to recognize rights that have no concrete textual support, like abortion or gay marriage, the originalist will also fiercely defend rights that do have textual support. That’s why Scalia, despite his vociferously right-wing views, often sided with his liberal colleagues on issues of free speech and criminal procedure. For instance, he cast the deciding vote in Texas v. Johnson, which held that the First Amendment protects the right to burn the flag, even though he later remarked that “if it were up to me, I would put in jail every sandal-wearing, scruffy-bearded weirdo who burns the American flag.”

It is precisely because of these principled limits that the rightmost wing of the conservative legal movement has begun to express discontent with originalism and renewed their interest in natural law. After all, Bostock—the case that found that the Civil Rights Act protects gay and transgender people—was a straightforward application of originalist reasoning. The opinion reasoned as follows: (1) the text of the Civil Rights Act prohibits employers from “discriminat[ing] against any individual … because of such individual’s … sex”; (2) that means an employer can’t fire a person of one sex for doing something if it wouldn’t fire a person of the opposite sex for doing the same thing; (3) an employer wouldn’t fire a man for having a romantic encounter with a woman; (4) therefore, if the employer fired a woman for having a romantic encounter with a woman, that would be discrimination “because of” sex.⁴ Bostock focused on the text of the statute—a form of positive law—and eschewed any inquiry into the “intent” of the law. 

Indeed, the main quarrel that uber-right-wing legal scholars have with originalism is that it’s too positivist. In his screed against Bostock, Horvat argued that originalism pays too much heed to positive laws that conflict with God’s will. Under originalism, he wrote, “law becomes merely the mechanical rules that keep society running smoothly, not the product of a divinely ordained order.”

Adrian Vermeule is the most prominent legal scholar to pivot to natural law. Vermeule was never a staunch originalist—his early work is more an argument for a weak judiciary than anything else—but he was originalist enough to clerk for Scalia. That changed over the past few years. In 2020, Vermeule wrote an infamous Atlantic article in which he argued that although “allegiance to the constitutional theory known as originalism has become all but mandatory for American legal conservatives,” the doctrine has “served its purpose.” Instead, Vermeule pitched a version of natural law called “common-good constitutionalism,” under which judges should use “principles of objective natural morality” to inform their decisions.

The Atlantic article is remarkable for its casual creepiness. Vermeule bragged that one advantage of his system is that it “does not suffer from a horror of political domination and hierarchy, because it sees that law is parental, a wise teacher and an inculcator of good habits.” Although he acknowledged that this could result in “legal strictures possibly experienced at first as coercive,” he wrote that over time, citizens would “form more authentic desires for the individual and common goods, better habits, and beliefs that better track and promote communal well-being.” (Of course, the “authentic” desires people will develop happen to coincide exactly with Vermeule’s own desires.)

If that sounds crazy to you, just wait. It turns out Vermeule’s Atlantic piece was the restrained version of his theory. Vermeule, like many proponents of natural law, is an ardent Catholic, to such an extent that he denies the legitimacy of other Christian denominations. In a 2016 interview, he said, “there is no stable middle ground between Catholicism and atheist materialism.” Vermeule has espoused a worldview called “integralism” which rejects the separation between church and state and suggests that Catholics should work toward a government run by the Vatican. In a blog post, he proclaimed that the end goal of his legal scholarship was “the eventual formation of the Empire of Our Lady of Guadalupe, and ultimately the world government required by natural law.” Yikes.

Into the Depths

Not only is natural law theory frighteningly undemocratic; it’s also fundamentally incoherent. It simply doesn’t hang together as a philosophy.  

Let’s start with some basic questions. Assume, for the moment, that “natural law” exists. Assume also that people can discover it. How? And what happens if two people disagree about what the natural law is?

The most thorough attempt to answer this question comes from John Finnis, Gorsuch’s dissertation adviser and the foremost living natural law scholar. Broadly, Finnis argues that natural law protects “basic values” or “goods” common to all human beings. A rule that promotes basic values is consistent with the natural law; a rule that inhibits them is not.

That reasoning, of course, just kicks the can down the road, because how are we supposed to decide what qualifies as “basic values”? Finnis answers this question with a concrete example. He begins with “knowledge,” which he posits as a basic value. All humans, Finnis contends, innately desire knowledge because we are curious about things—we want to “find out about something just for the sake of knowing.” For example, I might want to know the name of the fifth Spice Girl. With this empirical observation, we can formulate what Finnis calls a “practical principle”: “knowledge is something good to have.”

This reasoning is already muddled. How do you go from “what was the name of the fifth Spice Girl again?” to “knowing the name of the fifth Spice Girl is something good for everyone to have”?

But now Finnis really goes off the rails. The “practical principle,” Finnis argues, is evidence that

knowledge is really a good, an aspect of authentic human flourishing. … It seems clear that such indeed is the case, and that there are no sufficient reasons for doubting it to be so. The good of knowledge is self-evident, obvious. It cannot be demonstrated, but equally it needs no demonstration (emphasis mine).

Pause for a moment and mull this passage over. What it boils down to is this: the best Finnis could come up with to justify the existence of the universal “goods” on which natural law rests is, “I mean, isn’t it obvious?”

Obviously not. Later in his chapter on knowledge, Finnis quotes with approval Aquinas, who wrote “[a]ll knowledge is obviously good.” But anyone with a brain knows that some knowledge is obviously bad. If I set kittens on fire because I’m curious what burning fur smells like, even if I satisfy my curiosity, no “good” has come about.

The incoherence runs deeper. For the moment, let’s spot Finnis that knowledge is a universal good. What about a more controversial example, like spirituality? For some people, spirituality is an indispensable part of their lives, and those people would probably say it’s a self-evident good. (Finnis falls in that camp, positing “religion” as a “basic value.”) Other people don’t find spirituality “obviously” valuable. A crisis emerges: spirituality is self-evident as a good only to some people.

Worry not, because Finnis has a brilliant solution (lifted straight from Aquinas). Sure, he concedes, the value of fundamental goods isn’t obvious to everyone. But that doesn’t mean they’re not fundamental goods. Instead, some “propositions are self-evident only to ‘the wise,’ since only the relatively wise (or learned) understand what they mean.”

It’s a neat trick: if you disagree with Finnis, you’re just not wise enough for his point to be self-evident to you. Sorry.⁵

At least Finnis is honest about his methodology. Other natural law theorists reach the same point in sneakier ways. For example, Vermeule—the Harvard Law professor trying to establish a global “Empire of Our Lady of Guadalupe”—has been consistently mealy-mouthed about whether there’s any sort of objective basis for his idea of the “common good.” In his Atlantic article, he threw out “the ius gentium” and “the early modern theory of ragion di stato” as possible “sources” for the common good. These references are puzzling, but Vermeule’s rhetorical strategy is not; by throwing around obscure foreign phrases, he hopes to trick the reader into thinking there’s some solid intellectual pedigree for his theory. But even a cursory inquiry into the meaning of these phrases reveals the vacuity of Vermeule’s reasoning. Ius gentium is a natural law theory from ancient Rome that primarily concerned inter-state activities like war and diplomacy, so it’s unclear how it plays into Vermeule’s vision. Ragion di stato is the title of a 16th-century manuscript by a Jesuit priest which argued that the Church should form the backbone of civil government and a ruler “must prostrate himself in all humility before the Divine Majesty.”⁶ A creepy allusion, but not a source of jurisprudential insight, unless you count “the Church should run the government” as an insight.

In a speech at a conservative think tank, Vermeule was a little more honest about how his system might work in practice. Invoking Aquinas (see how he keeps popping up?), Vermeule argued that natural law is a matter of “the art or craft of practical reasoning.” A “judge cannot simply recline back into some sort of general skepticism about the common good or its determinacy, intoning ‘who decides?’” Vermeule said. “For legal purposes, the jurists decide.”

There’s “practical reasoning” again. When a judge engages in “practical reasoning,” she applies her own experiences and sense of right and wrong. So to the extent this means anything, it means that “common-good constitutionalism” will be the sum of common-good constitutionalists’ beliefs. As with Finnis, lurking under Vermeule’s academic jargon is an appeal to unverifiable personal convictions.

To be clear, I don’t have a problem with judges sometimes relying on personal moral beliefs. If a duly-enacted statute forbade people from harboring escaped slaves, or mandated sterilization of the intellectually disabled, or put everyone of a certain ethnicity into internment camps (all real examples), judges should say “I won’t enforce that law, it’s wrong.” But there’s a crucial distinction between using personal morality as a backstop against a patently evil law, and claiming personal morality is the law. Natural law, at bottom, reflects that latter position—and that’s what makes it so dangerous.

One more example confirms the point. In the ‘90s, Gorsuch penned a law journal article arguing that physician-assisted suicide should be illegal. The article discusses several arguments that proponents of assisted suicide often cite, like arguments based on fairness or bodily autonomy. Gorsuch tries to rebut each of these arguments, and ultimately concludes that it’s impossible to “resolve end-of-life questions objectively.” Instead, he says “a necessarily subjective conception of right and wrong is required.”

So far, so good. If the morality of assisted suicide is “necessarily subjective,” then we should leave end-of-life decision to patients and their doctors—right?

Wrong! Gorsuch inexplicably backtracks, arguing that “there are certain irreducible and categorical moral goods and evils” which are “fundamental aspects of human nature.” And life, per Gorsuch, is one of those fundamental goods. Ergo, “the intentional taking of human life by private persons is always wrong.”

The article is a marvelous exercise in cognitive dissonance. Gorsuch surveys and rejects purportedly objective criteria for evaluating assisted suicide; concedes that “end-of-life questions” require a “subjective conception” of good and evil; articulates an (unverifiable) subjective belief that life is always good; and claims that this justifies banning assisted suicide. Or, to summarize his argument more succinctly: assisted suicide is wrong… because I said so.

All this reminds me of an old joke. A scientist gives a public lecture about astronomy, explaining that earth is a big rock hurtling through space. After the lecture, a woman approaches him and says, “Your theory is very nice, professor, but I’ve got a better one. I think the earth stands on the back of a giant turtle.” The professor politely asks, “But ma’am, what does the turtle stand on?” “Why, that’s easy,” the woman responds, “another, bigger turtle.” “But what does the second turtle stand on?” the scientist queries. The woman laughs. “You can’t fool me, professor—it’s turtles all the way down!”

The parallels are obvious. Natural law philosophy: “The law derives from fundamental goods.” You: “How do you establish fundamental goods?” Natural law: “Fundamental goods are self-evident, and if you disagree, you’re stupid.” It’s fundamental goods all the way down. The only self-evident truth in all of this is its circularity. Natural law philosophy ends, after a meandering journey, where it started: the personal convictions of the natural law philosopher.

De Influentia Philosophiae

One of the first and best longitudinal surveys of American jurisprudence is The Common Law, an 1881 treatise by future Supreme Court justice Oliver Wendell Holmes Jr. Holmes wrote that when judges decide legal issues, they have many analytical tools at their disposal: the text of the law, default rules for interpreting that text, the reasoning in prior cases, statements by Congress or another legislative body, abstract theories about the law, and their own common sense. Different tools sometimes point to different outcomes, and there’s often no clear framework for prioritizing one tool over another. So, according to Holmes, judges usually make an ad-hoc determination about which tool produces a “reasonable” outcome in the case before them.

At first blush, that seems to suggest that the rise of natural law jurisprudence doesn’t matter: if judges decide the result of a case and then pick a justification, of what import is the justification?

But actually, I think the opposite is true. By its very nature, a legal philosophy holds that judges should prioritize some analytical tools over others. And if a legal philosophy becomes embedded in the institutions that shape our legal system—law schools, courts, public discourse—that philosophy can cause decision-making norms to drift, slowly and inexorably reshaping the legal landscape.

Originalism, the conservative legal philosophy that natural law theorists aim to displace, is a perfect example of this phenomenon. Back in the day, when judges had to decide the meaning of words in a law, they engaged in a meandering hunt for the “intent” behind the words. The poster child for this approach is the 1873 Supreme Court decision in the so-called Slaughterhouse Cases. The Court was tasked with interpreting the relatively new 14th Amendment, which, among other things, prevents states from “deny[ing] to any person within its jurisdiction the equal protection of the laws.” Louisiana had passed a law granting one company an exclusive monopoly on slaughterhouses. The plaintiffs, a group of butchers whose livelihood the monopoly destroyed, argued that the law violated the “equal protection” clause by treating them differently from the monopoly-holder. 

The Court summarily rejected that argument. It wrote that there was only “one pervading purpose” in the 14th Amendment, namely “the freedom of the slave race, the security and firm establishment of that freedom, and the protection of the newly made freeman.” Thus, though the Court acknowledged that the 14th Amendment doesn’t even mention Black folks or freed slaves, it wrote: “[w]e doubt very much whether any action of a State not directed by way of discrimination against the negroes as a class, or on account of their race, will ever be held to come within the purview of this provision.”⁷ Intent, in other words, trumps text.

A century later, the Court applied the same loosey-goosey procedure in Griswold v. Connecticut, the case that established a constitutional right to privacy. But this time, the Court ignored the text in order to expand, rather than contract, constitutional rights. It acknowledged that the word “privacy” appears nowhere in the Constitution. But, per the Court, the “specific guarantees in the Bill of Rights have penumbras, formed by emanations from those guarantees,” and a right to privacy emerges from those “penumbras and emanations.”⁸ Not for the first or last time, the Court made law based primarily on a vibe check.

Things are very different now, mostly due to originalism. In the ‘70s and ‘80s, a group of conservative jurists began to attack the earlier, freewheeling way of interpreting the law. They argued that it’s unprincipled and undemocratic for judges to ignore the text of the laws they’re asked to interpret. After all, the text is the product of the democratic law-making process; to base a decision on non-textual factors would convert judges into philosopher-kings. Originalism shifted the priority of analytical tools, obliging judges to center their analysis of the law on the relevant text. 

This view has been incredibly influential, and not just among conservatives. Nowadays, virtually every judge starts—and often stops—with the text of the law. If you wrote a brief invoking “penumbras and emanations,” you’d be laughed out of court. Justice Kagan, one of the three liberals on the Court, summed up this sea change with a quip at her confirmation hearings: “We’re all originalists now.”

Originalism shows that when a legal philosophy becomes popular, over time, it can work deep structural change on American jurisprudence. That’s what Vermeule and his ilk want natural law to do.

Vermeule’s article hints darkly at what that would entail. Originalism, he wrote, “has prevailed, mainly because it has met the political and rhetorical needs of legal conservatives struggling against an overwhelmingly left-liberal legal culture.” But

circumstances have now changed.  The hostile legal environment that made originalism a useful rhetorical and political expedient is now gone. … If President Donald Trump is reelected, some version of legal conservatism will become the law’s animating spirit for a generation or more; and even if he is not, the reconstruction of the judiciary has proceeded far enough that legal conservatism will remain a potent force, not a beleaguered and eccentric view.

Turns out originalism was nothing more than an effective way for right-wingers to play defense in an era of legal reform. And now that they’ve “reconstructed” the judiciary and infiltrated the academy, it’s time to go on the attack.

What might that look like? The possibilities are far-reaching. Take abortion. Last year, the Court overturned Roe and eliminated the constitutional right to abortion—a triumph of originalism. But 20 or so  states still protect the right to abortion, either by statute, state-court precedent, or constitutional provision. What happens if the GOP seizes control of Congress and passes a nationwide abortion ban—a strategy Lindsey Graham has already floated?

A sincere originalist would probably say that’s a bridge too far. The power of Congress to regulate interstate commerce, though vast, does not extend to purely intrastate medical procedures—at least, not under the original public meaning of the text of the commerce clause.

That concern wouldn’t matter to natural law theorists. According to Vermeule, Finnis, and Gorsuch, the law is “parental, a wise teacher and an inculcator of good habits” and exists to protect “basic, self-evident values” and “irreducible and categorical moral goods”—like life. If performing an abortion is taking a life, then the State—the “parental, wise teacher”—must be able to forbid it. Indeed, per Aquinas, any regime of positive law that fails to forbid conduct that contravenes the law of nature is “is no longer a law but a perversion of law.”

Natural law, in short, has terrifying potential to serve as a legal fig leaf for reactionary, paternalistic legislation. Indeed, the GOP seems to be paving the way for efforts to ban many regarded as “unnatural” by traditional theology. The Texas GOP recently declared homosexuality to be an “abnormal lifestyle choice,” and stated its “official position” that “there are only two genders.” It’s a short leap from there to “homosexuality and transgenderism are unnatural.” Couple that with a legal philosophy that justifies state enforcement of theocratic morality—and all of us are in for a bad time.

1. See United States v. Tsarnaev (Barrett voted to reinstate the death penalty for the Boston Marathon bomber) and Dobbs v. Jackson Women’s Health Organization (Barrett voted to end the constitutional right to abortion). ↩

2. St. Thomas Aquinas, The “Summa Theologica” Part II (London: R&T Washbourne, Ltd., 1915). ↩

3. Antonin Scalia, A Matter of Interpretation, (Princeton, NJ: Princeton University Press, 2018). ↩

4. Bostock v. Clayton County, Georgia, 140 S. Ct. 1731 (2020). ↩

5. John Finnis, Natural Law & Natural Rights, Second Edition (Oxford: Oxford University Press, 2011). ↩

6. Giovanni Botero, The Reason of State, trans. P.J. Waley and D. P. Waley (New Haven: Yale University Press, 1956), 63. ↩

7. Slaughterhouse Cases, 83 U.S. 36 (1872). ↩

8. Griswold v. Connecticut, 381 U.S. 479 (1965). ↩