Further Thoughts on Substantive Due Process

Robert Black
14 min readJan 18, 2022


So I got in a slight Twitter spat today, concerning the new book The Original Meaning of the 14th Amendment: Its Letter and Spirit, by Evan Burnick and Randy Barnett. (Yes, that Randy Barnett.) More specifically the spat concerned a review of Burnick and Barnett’s book by one Eric Seagall, a legal-realist law professor known among other things for his criticism of originalism (see e.g. his book Originalism As Faith).

I felt that Seagall’s review confirmed the impression I got of the Burnick/Barnett book from its initial publicity, namely that for all its claim to revolutionize our understanding of the Fourteenth Amendment, it doesn’t really add anything new to the conversation. A broad reading of the Privileges or Immunities Clause, both incorporating the Bill of Rights against the states and protecting a broader array of unenumerated rights, placing that Clause at the center of the Amendment; a relatively more minor role for both the Due Process Clause (which has been made the principal vehicle for protection of substantive individual rights against the states given the gutting of the Privileges or Immunities Clause in The Slaughter-House Cases) and the Equal Protection Clause (which is seen on this model as concerned largely with the even-handed application of general criminal laws and the like, with P/I again doing much of the substantive work of guaranteeing equality): all of this is exactly what I learned from Akhil Amar and Steve Calabresi not only in law school but as an undergrad at Brown. Of course it is true that this model barely resembles the Supreme Court’s understanding of the Amendment, but people have been making that exact point for a while now.

There was one part of Burnick and Barnett’s position, as relayed by Seagall, that did stand out to me, though:

Now I took this to mean that Burnick and Barnett thought the Due Process Clause of the Fourteenth Amendment imposed a requirement that state laws, notably including general economic regulations like those upheld in Williamson v. Lee Optical, must not be “arbitrary,” and that this requirement should be enforced by judges through “a real and more searching rational basis review.” In particular the turn of phrase here, “there must be a judicial proceeding … before a state deprives anyone of life, liberty or property in an arbitrary manner.” That’s weird, right? Shouldn’t the rule just be “no arbitrary deprivations,” and then, since it’s coming from a Due Process Clause, what that means is “no extrajudicial deprivations”?

I said as much on Twitter, and Seagall jumped in to correct me: it seems instead that Burnick and Barnett locate the substantive rule against arbitrary lawmaking in the Privileges or Immunities Clause, and the role of the Due Process Clause is simply in emphasizing the role of the judiciary in enforcing that rule. Fair enough! That is a more coherent position to take, and I said so, and that seemed to satisfy Seagall.

What I didn’t say is that I think this position is completely wrong. So I want in this post to explain both why I originally interpreted this passage from Seagall’s review the way I did, and why I think Burnick and Barnett, as I now understand their position, are wrong. Of course I still haven’t read their book, and frankly I am not likely ever to do so; as I said I feel increasingly that they only confirm what had already been my view of things, and let’s just say that having Randy Barnett on the byline is not something I find enticing. So perhaps I should not say I am explaining why Burnick and Barnett are wrong, but just why I do not think the position Seagall ascribes to them is correct.

First, why did I think they were grounding the rule against arbitrary laws in Due Process? Well partly because there is a very long history of people, and the Supreme Court in particular, doing just that. But it’s not just the history: there’s a kind of logic to it. How do you get substantive rules of constitutional law from the text “No state shall … deprive any person of life, liberty, or property without due process of law?” The substantive due process cases will say things like “the liberty protected by the Fourteenth Amendment includes blah blah blah.” But the Amendment does not, by its terms, guarantee “liberty” against anything except deprivation without due process of law. We send people to prison after judicial trials, after all, a much graver deprivation of liberty than preventing them from contracting for a low wage or from using contraception: process is all that is required.

Well here is how you might go about reaching this conclusion, if you were so inclined (perhaps because the Court gutted the more natural vehicle for protecting individual rights). The Due Process Clause does not merely prevent extrajudicial punishments; it imposes a quality standard on the kinds of proceedings that are used to effect deprivations. We might reasonably think that “due” process means, at a minimum, the full gauntlet of procedural rights guaranteed in the latter portion of the Bill of Rights, trial by jury and the like. A supposedly judicial proceeding that does not abide by those guarantees is not the kind of process which people are due.

And there is another requirement that we might reasonably think of the Due Process Clauses as imposing on the quality of the judicial process, though it is never mentioned in the text: that adjudication must be reasoned rather than arbitrary. If it were proposed that cases be decided literally at random, we would rightly say that the Due Process Clauses forbade such a thing. If an Act of Congress provided for random adjudication, we should consider it null and void under the Fifth Amendment. If a federal judge were known to decide randomly, they should be removed from the bench by impeachment. If state courts were known to employ random decision, whether by statute or by judicial habit, we should think that the Fourteenth Amendment’s Due Process Clause afforded a federal judicial remedy to those afflicted by the practice. An individual whose sentence was determined avowedly at random, for example, would be able to bring a federal habeas corpus action.

The rule against arbitrary adjudication may sweep more broadly than outright randomness, but that example helps show that this is indeed a rule of constitutional law we should recognize and defend. And once we have done so, it is but a short step to saying that it is not enough for the court system to be rational rather than arbitrary: should not the very law according to which people are deprived of their life, liberty, or property be rational as well? If it is rationally determined that someone has violated an irrational law, can we call the entire proceeding rational rather than arbitrary? Hence the Clause comes to be understood to protect “liberty” against abrogation by irrational statute, not only against irrational judgments.

But although there is a logic here, it is a deeply flawed logic. To apply the Due Process Clause to substantive law is to misapprehend the role of due process in a constitutional republic. The oldest version of the Due Process Clause, in Magna Carta, required that deprivations of life, liberty, or property by “by the law of the land.” And this is very much the function of forbidding extrajudicial punishment. The very idea of democracy imposes certain restrictions on what the law of the land can be: chiefly, it can only be made by the People through their chosen representatives; but more than this, it must not transgress certain fundamental individual rights without which the society could not be truly democratic.

But if the executive has an unchecked power to imprison anyone they judge to have violated the laws, there can be no guarantee that the thing being enforced is actually the law of the land. We say that, in a democracy, it cannot be made a crime to criticize the state. But without a requirement of due process, it will not matter that there is no seditious libel statute on the books. The executive can simply imprison anyone who does criticize the state on trumped-up charges of violating some other law. More broadly, they could usurp the entire legislative power, enforcing not the statutes passed by the elected legislature but their own will. The requirement of judicial process prevents this: in order to carry out a punishment, the executive must convince an independent tribunal (and possibly a lay jury) that the accused really did commit the violation of which the executive has accused them. It ensures that the machinery of punishment and deprivation is actually used to enforce the law of the land, rather than for some more nefarious purpose.

Of course due process, understood in terms of this function, says nothing about the substance of the laws being enforced. Oh, there may be other constitutional prohibitions on substantive law (e.g. the rule against making seditious libel a crime) that due process will vindicate. But it makes no sense to speak of primary legislation violating due process rather than some other independent prohibition. (Of course legislation providing for inadequate judicial process may violate a guarantee of due process; hence the qualifiers.)

Anyway. That is why we should not make the Lochnerian leap, of insisting that legislation follow the same norm of rationality that we expect of adjudication. (In fact, the legislative power’s ability to act without giving reasons is every bit as characteristic as the judicial power’s inability to act without reason-giving.) “Substantive due process” is every bit as much the contradiction in terms that it sounds at first blush. But the Privileges or Immunities Clause really does provide direct limits on the scope of substantive law. It is therefore entirely coherent to say that the Privileges or Immunities Clause imposes a general requirement of rationality: we could say that citizens of the United States are privileged against living under irrational and arbitrary laws.

But I think it’s equally wrong. Let’s start by noting that, whereas the concept of Due Process really does put the idea of rationality as a touchstone into one’s head, there is nothing about the language of the Privileges or Immunities Clause that does so. “No state shall make or enforce any law abridging the privileges or immunities of citizens of the United States”: this suggests to me some specific zones of individual freedom into which the states simply cannot transgress, regardless of their reasoning. Again the example of seditious libel makes a suitable example: the states cannot make it a crime to criticize the government, and they cannot do this no matter how rational their desire to do so may appear — say, if there is a war on, and it is felt that such criticism might compromise morale and therefore compromise the war effort. Totally rational! Also totally forbidden. Admittedly this way of doing constitutional law is not very fashionable these days, but it’s what the language suggests.

We can go further. There is sound reason to think that the Privileges or Immunities Clause was intended, at the very least, to require the states to abide by the federal Bill of Rights. Does the Bill of Rights contain a general rule against arbitrary lawmaking by Congress? It’s hard to see where. I suppose if we thought that due process imposed such a requirement then we could locate it in the Fifth Amendment, but we have already rejected that idea. None of the other provisions seem remotely applicable: each imposes a specific prohibition against doing a specific kind of thing.

Ah, but what of the Ninth Amendment? It tells us that the first eight amendments do not exhaust the scope of individual rights against the government. And so it might be thought to say, in the context of the Fourteenth Amendment, that not only the express provisions of the first eight amendments are privileges or immunities of citizens, but that a broader field of rights are included. (Sorry Hugo Black.) Might not this general field of unenumerated rights include the right against arbitrary legislation?

Anything is possible I guess, but there is no real reason to think that it would. People are resistant to the idea that there is a method for determining the scope of Ninth Amendment rights. But I think there is a pretty plausible account, both of how the Ninth Amendment itself is supposed to work and of how it relates to the Fourteenth Amendment. The Ninth Amendment is pretty clearly James Madison’s brainchild, and it pretty clearly arose out of the debates during ratification about the necessity of the Bill of Rights. During that debate, Madison had claimed, along with other Federalists, that a bill of rights was unnecessary. States had bills of rights because their legislatures possessed plenary power, and therefore in order to achieve liberal, limited government that power must be subjected to specific limitations. But the new federal government would possess enumerated rather than plenary legislative power: it was, in other words, inherently a government of limited power, without any need to impose the positive limits of a bill of rights. As Hamilton said in Federalist № 84, “the Constitution is itself, in every rational sense, and to every useful purpose, A BILL OF RIGHTS.”

Indeed Madison, like Hamilton, thought not only that a bill of rights would be unnecessary but that it would be positively dangerous. Again in Hamilton’s words:

I go further, and affirm that bills of rights, in the sense and to the extent in which they are contended for, are not only unnecessary in the proposed Constitution, but would even be dangerous. They would contain various exceptions to powers not granted; and, on this very account, would afford a colorable pretext to claim more than were granted. For why declare that things shall not be done which there is no power to do? Why, for instance, should it be said that the liberty of the press shall not be restrained, when no power is given by which restrictions may be imposed? I will not contend that such a provision would confer a regulating power; but it is evident that it would furnish, to men disposed to usurp, a plausible pretense for claiming that power.

Now these arguments did not carry the day during ratification; approval in key states was plainly conditioned on the expectation that a bill of rights would be adopted after ratification. Indeed Madison himself seems to have been persuaded by the arguments favoring a bill of rights; he certainly took up the role of crafting the Bill with enthusiasm. But he did not entirely abandon the position quoted at length above, and that is why we have the Ninth Amendment. It exists specifically to cut off the inference that Hamilton thinks a bill of rights might give rise to. Or to put it another way, it is meant to preserve the vitality of the line of reasoning by which the Federalists thought the enumeration of federal power had already provided ample protection for individual rights.

Now trying to understand the Ninth Amendment in this fashion is somewhat complicated by the fact that Madison and Hamilton were plainly wrong about what enumeration had accomplished. Hamilton says no power is given by which liberty of the press might be restricted, but this is clearly wrong: interpreting the enumerated powers only literally and narrowly, Congress could pass a law forbidding the interstate shipment of newspapers critical of the government. So in order to affirm the Federalist vision of enumeration as a bill of rights, we need to import into our interpretation of the enumerated powers some kind of implicit limitations. The express provisions of the Bill of Rights can light the way, at least to a degree, but the Ninth Amendment tells us that the implicit limits on federal power are not particularly tied to those provisions. This is basically where Philip Bobbitt’s idea of argument from constitutional ethos is in its element.

In any event, suppose we think that the Privileges or Immunities Clause incorporates not only the first eight amendments but the Ninth as well against the states. What can this mean? States have plenary powers, not enumerated powers; that’s exactly why the Federalists thought we didn’t need a federal bill of rights! Bobbitt says that the basic error of the Lochner Era was in trying to accomplish this by imposing on the states a uniform constitution of enumerated powers — the so-called “police power,” defined in those days as the power to protect the “health, safety, morals, and welfare” of the people. Anything not covered by that formula, anything not rationally related to one of those ends, was considered outside the scope of state power. But this is silly: states do not have enumerated powers, and nothing in the Fourteenth Amendment purports to change this! Instead it subjects their plenary powers to a federal set of limitations, supplementing whatever protections for individual rights might already exist at the state level.

Bobbitt’s proposed solution to this is to speak of means rather than ends: the Fourteenth Amendment forbids the states from using, in the exercise of their plenary powers, those means which the federal government is forbidden from employing in the exercise of its enumerated powers. The method of reasoning that we would have used to say that a law against the interstate shipment of opposition newspapers was an improper exercise of the Commerce power, even in the absence of the First Amendment, and that we might use to generate other implicit limits on federal power, we should also use to discover the limits on state authority.

Now we can ask, with somewhat more defined parameters, whether we ought to think the Ninth Amendment, as adopted into the Fourteenth, includes a general rule against arbitrary lawmaking. I think the answer is “no,” certainly if by that we mean a rule with “teeth” of the sort Burnick and Barnett seem to want. Congress is understood to have a broad choice of the means it uses to effectuate its ends; this is among other things the meaning of the Necessary and Proper Clause. And McCulloch v. Maryland stands for the proposition that the judiciary is not, generally speaking, to second-guess Congress’s judgment as to the necessity of a particular means. Indeed the famous formula from McCulloch serves as a nice guide for how to go about the sort of reasoning that the Ninth Amendment calls for:

Let the end be legitimate, let it be within the scope of the Constitution, and all means which are appropriate, which are plainly adapted to that end, which are not prohibited, but consist with the letter and spirit of the Constitution, are Constitutional.

On this formulation, courts can absolutely invalidate measures that are prohibited by the Constitution, and they even possess a significant authority to inquire into the spirit of the Constitution to discern prohibitions not immediately apparent from the text. But they have decidedly minimal authority to inquire into the basic rationality of the law. All they can ask is whether the measure is “plainly adapted” to achieving some legitimate end; in other words, to look for pretext (as we might understand the law against shipment of opposition newspapers to be pretextual). Of course it could have been decided to adopt a more stringent test for congressional power, but it was not. And if the limits on state power are to be analogous in some fashion to the limitations on federal power, they are presumably to be analogized to those limits as they actually exist in our system, not as they might exist in some alternate vision of the federal system preferred by Randy Barnett.

This concludes the inquiry. There is simply no good reason that I can discern for interpreting the Privileges or Immunities Clause of the Fourteenth Amendment, or for that matter any other provision of the Constitution, as imposing a general rationality requirement on state legislation. The text of the Clause does not call such a requirement to mind; the federal Bill of Rights, generally understood as its minimum intended content, does not impose such a requirement; and the method of implied limitation recognized by the Ninth Amendment does not support such a rule, as it has never been understood to apply in the domain of federal power.