In a pair of cases set for argument in January, the U.S. Supreme Court has been asked to overrule Chevron U.S.A. Inc. v. Natural Resources Defense Council, Inc. I’m going to suggest that whether Chevron should be overruled isn’t exactly the right question. That’s because Chevron—at least the part of it that most people are interested in—didn’t make binding law in the first place.
There’s no need to dwell on whether the doctrine of stare decisis permits a departure from Chevron. The real question (and one on which I take no position) is what guidance the Justices should offer to judges faced with complex statutory schemes in spaces regulated by federal agencies.
Calls to overrule Roe v. Wade generally were focused on abortion—as are more recent calls to overrule Dobbs v. Jackson Women’s Health Organization. Calls to overrule Citizens United v. FEC generally are focused on corporate electioneering. Calls to overrule District of Columbia v. Heller generally are focused on guns. But most calls to overrule Chevron have little to do with air pollution, which was at the center of the case.
The pending challenges to Chevron are illustrative: they involve the regulation of commercial fishing vessels. That dissonance is our first clue that “overruling Chevron” doesn’t mean what one initially might think.
As a practical matter, to dispute Chevron is to contest neither the Supreme Court’s interpretation of the Clean Air Act Amendments of 1977 nor its assessment of the position taken by the Environmental Protection Agency in that case. The target of criticism, rather, is the interpretive protocol that the Chevron Court employed. At base, the protocol entails upholding an agency’s interpretation of an ambiguous statute so long as the interpretation is reasonable. Getting rid of Chevron means rejecting that protocol and instructing courts to reach their own interpretive conclusions instead of deferring to agencies.
The Stakes of Chevron
If the Chevron test is indeed binding law—which is how it’s customarily treated—its implications depend on the level of the judicial hierarchy that we’re talking about. In the lower federal courts, the test is compulsory, leaving judges no option but to apply it. Statutory ambiguity begets deference to agency interpretations, even if a judge thinks an alternative reading is more plausible.
The dynamics are different at the Supreme Court, which has authority to reconsider its own precedents. Treating the Chevron test as binding law in the Supreme Court means giving it presumptive deference and demanding a “special justification,” above and beyond its merits, before rejecting it. The Court’s doctrine of stare decisis encompasses a variety of factors designed to inform that analysis. If the Chevron test is binding, its fate at the Supreme Court depends on the application of those factors.
By contrast, if the Chevron test isn’t binding, lower courts may depart from it in any given case. So, too, may the Supreme Court—and without need to apply the doctrine of stare decisis. That makes it crucial to determine whether Chevron’s test really is binding law.
The Scope of Chevron
Every Supreme Court precedent contains some parts that are binding and some parts that aren’t. Deciding which parts are which is an exercise in defining the scope of precedent, meaning the universe of propositions for which a judicial opinion stands as legal authority.
Defining a precedent’s scope usually begins with separating its binding holding from its extraneous dicta, or by reflecting on its ratio decidendi (roughly speaking, its rationale). But as I’ve explained in other work, those concepts aren’t always enough.
Chevron is a case in point. That decision certainly created a binding precedent with respect to its interpretation of the relevant statute and its application of the statute to the administrative action under review. The Chevron Court’s interpretive protocol is another matter. To be sure, that protocol was necessary to the case’s outcome in some sense. Consider, though, the profound implications of infusing the protocol with binding force. The Chevron test is not limited to any particular statute or any particular administrative agency. Its sweep is capacious and trans-substantive. If the test really is binding, it tells future judges how they must interpret countless statutes involving countless agencies.
A judge who is obliged to apply the Chevron test already knows what he must infer from statutory ambiguity—not simply with respect to the Clean Air Act, but across the board. No matter when a statute was enacted, what subject matter it covers, or which administrative agency it implicates, the presence of ambiguity demands one and only one conclusion: Congress intended to give discretion to the agency. This is a bracingly expansive assumption to impose upon the entire federal judiciary. And it is striking to think that the Supreme Court has the authority to insist on such an assumption pursuant to its constitutional power to resolve discrete cases and controversies. (I develop this argument further in a 2019 article.)
Chevron is far from the only case that raises slippery questions about the scope of judicial precedent. This very Term, the Supreme Court is considering the standard for adjudicating constitutional challenges to firearm regulations. Recently, in New York State Rifle & Pistol Association, Inc. v. Bruen, the Justices instructed courts to determine whether a law is “consistent with the Nation’s historical tradition of firearm regulation.” Again, it’s quite clear that the Justices had the power to adopt and endorse such an approach—not to mention the power to reverse lower courts who fail to heed their advice. Whether the Justices possess the authority to insist on what is effectively a commitment to the originalist methodology is a more difficult question (and one that I discuss here). Framed as studies in precedential scope, Chevron and Bruen share a fascinating, and complicated, connection.
Back to Chevron
Chevron is binding law with respect to its interpretation of a specific statute—even an interpretation that the Supreme Court adopted for reasons sounding in deference—and its assessment of a specific administrative action. The same is true of subsequent Supreme Court decisions that applied the Chevron test in dealing with other statutes and other agencies. The test itself, however, stands on different ground.
Of course, judges and Justices are at liberty to apply the Chevron test if they find it persuasive. Moreover, lower court judges who harbor doubts about the test may nevertheless apply it if they believe that, based on their understanding of the judicial hierarchy, they should follow the Supreme Court’s guidance even when it falls outside the binding scope of precedent. Yet lower court judges ought not deem themselves inexorably bound to apply the Chevron test in contexts bearing little resemblance to Chevron itself. Nor must the Supreme Court ask whether the doctrine of stare decisis justifies the Chevron test’s revision or rejection.
Which brings us back to the beginning, and the pending challenges to Chevron. It is no mean feat to elucidate the respective roles of legislature, executive, and judiciary as they bear on the interpretation of knotty federal statutes—especially statutes whose precision leaves something to be desired. That is the task to which the Justices should devote their attention. There will be plenty of opportunities to apply the doctrine of stare decisis in cases where it belongs.
Randy J. Kozel is the Fritz Duda Family Professor of Law at the Notre Dame Law School.
 For discussion of which statutes the Chevron test governs, see United States v. Mead Corp., 533 U.S. 218 (2001).
 For present purposes, I make no claim about the Supreme Court’s power to exercise supervisory authority through other means, such as the promulgation of rules of practice and procedure.