I’ve just posted a revised version of my paper, Substantive Due Process And The Promise of Lawful Rule: A Conceptual Guide, on SSRN. This article is an attempt to explain the argument in favor of “substantive due process” (a misleading name in itself) less in terms of history than in terms of political philosophy and common sense. And I’ll be presenting the paper at the Loyola Constitutional Law Colloquium in Chicago in October.

The core of my argument is in part II, where I explain how “substance” and “procedure” can’t really be separated in the context of the due process clause. Since the due process of law principle requires government to act only in a lawful—i.e., authorized, non-arbitrary—manner, its acts qualify as “law,” and satisfy the due process requirement, only where those acts are within the government’s legitimate authority, and that includes both procedural and substantive limitations. Consider three brief examples.

(1) Suppose Congress were to enact a law, and the president vetoes it, but the local sheriff tries to enforce it anyway, arresting you for violating the provisions of this vetoed bill. You would naturally argue that the sheriff had no lawful authority to arrest you, since you’d broken no law. The sheriff is depriving you of liberty without due process of law.

(2) That’s an example where there’s a procedural shortcoming—the “law” in question lacks lawful authority because of some procedural failing. But there are substantive limits on legislative authority, too. So if Congress were to pass a bill—and this time the president signs it—which purports to establish a national religion for the United States, and forces you to attend church, this would violate the First Amendment. When the sheriff again shows up to arrest you for not going to the official church, you would rightly argue that this, too, is beyond the sheriff’s lawful authority. Congress has no power to make such a thing into a “law,” so you to be arrested under the alleged authority of such an invalid “law” would be to deprive you of liberty without due process of law. Not because of any procedural shortcoming, but because of an explicit substantive limit on Congress. This is “substantive” due process.

(3) But in addition to explicit limits on Congress, are there not implicit limits? Prohibitions on what the government can do that are not explicitly written down, but are nonetheless real—prohibitions either inherent in the text or so obvious that the framers didn’t think it even necessary to write them down? We know that there are implicit procedural limits on what Congress can do. In Clinton v. New York, the Supreme Court held that Congress cannot give the president a line-item veto, even though there’s no explicit prohibition on such a thing. The Court (rightly, in my view) held that the process described in the Constitution for how to pass a law is the exclusive process, so Congress lacks authority to create any alternative. Thus there are implicit procedural limits on what the government can do. So what about implicit substantive limits?

Imagine government as the founders did—as something like a bank guard, hired to protect your bank from being robbed. Now, imagine that he decides instead to use his position to rob the bank himself—an inside job. His acts lack any legitimate authority from the employment contract, even though the employer fails to write into the employment contract “do not rob my bank”! The contract implicitly forbids certain acts, regardless of process—that is, the nature of the contract determines the ends for which the delegated authority may be exercised: exactly the principle of substantive due process in cases like Loan Association v. Topeka or Lochner v. New York.

In fact, I was delighted to discover that there’s an actual case about a rogue bank robber that makes my point quite beautifully….

But for more on that, you’ll just have to read the article.