Litigants in our adversarial system must raise their best arguments or the court will find that the argument has been “waived” (or more precisely, “forfeited”). But what should courts do if an agency or a private party fails to raise Chevron deference during litigation about the lawfulness of agency action? In a forthcoming essay in the Stanford Law Review Online, we challenge the prevailing view that agencies and private parties may “waive” Chevron deference if they fail to invoke (or challenge) the deference regime. We argue that, as a general rule, courts should independently determine whether Chevron applies. This blog post builds upon that essay and considers whether our arguments against “Chevron waiver” also apply to other administrative law deference regimes: namely, Auer and Skidmore deference.

Courts frequently say that a litigant’s failure to raise her arguments under Auer or Skidmore constitutes waiver. Agencies can waive their entitlement to Auer by failing to invoke deference. See, for example, Massachusetts Mutual Life Insurance Co v United States, 782 F3d 1354, 1369 (Fed Cir 2015); Scheidelman v Commissioner of Internal Revenue, 682 F3d 189, 197 n 6 (2d Cir 2012). And private parties can waive their challenge to Auer by failing to dispute whether the agency deserves deference. See, for example, Maine Medical Center v Burwell, 775 F3d 470, 479 (1st Cir 2015). Courts apply the same logic to Skidmore for both agencies and private parties. See, for example, Pakootas v Teck Cominco Metals, LTD, 830 F3d 975, 986 n 12 (9th Cir 2016) (agency); Wisconsin Central Ltd v. United States, 194 F Supp 3d 728, 733 (ND Ill 2016) (private party).

Perhaps the most notable example of “Skidmore waiver” is the Tenth Circuit’s en banc decision in Hydro Resources, Inc v EPA, 608 F3d 1131 (10th Cir 2010) (en banc). In an opinion by then-Judge Neil Gorsuch, the majority reviewed the agency’s interpretation of a statute de novo—refusing to give even Skidmore deference—because the agency hadn’t “claimed any entitlement to deference” during the litigation. Id at 1146. In a footnote, the majority explained that “when a party chooses not to pursue a legal theory potentially available to it, we generally take the view that it is inappropriate to pursue that theory in our opinions.” Id at 1146 n 10 (internal quotation marks omitted). In dissent, Judge David Ebel wrote that he would review the agency’s interpretation under Skidmore—even though the agency “ha[d] not asked for such deference” in its briefing—because “a party’s concession on the standard of review does not bind the court, as such a determination remains for the court to make for itself.” Id at 1170 n 2 (Ebel dissenting) (cleaned up).

Our essay on Chevron waiver offers three reasons why Chevron deference may not be waived. First, legal propositions—such as binding precedents or interpretive canons—are generally not subject to waiver rules. Second, blackletter administrative law doctrine instructs that courts should look to the agency’s reasoning—not the litigator’s—when evaluating the lawfulness of agency action. Third, as a separation-of-powers matter, Congress and the courts (not litigants) should decide whether an agency’s interpretation does or does not warrant deference. Some of these arguments apply equally to other administrative law deference regimes, but others do not.

The primary similarity between Chevron, Auer, and Skidmore is that all three deference regimes are legal doctrines, which aren’t usually subject to waiver rules. Whether one characterizes Chevron as a binding precedent, a standard of review, or an interpretive canon, deference shouldn’t be waivable—in the same way that a court wouldn’t ignore a relevant precedent or disregard the ordinary meaning canon just because a party had failed to brief the issue. The same principle extends to Auer and Skidmore. Indeed, Judge Ebel’s dissent in Hydro Resources makes this basic point by analogizing Skidmore to a standard of review.

Unlike our arguments from waiver doctrine, however, our administrative law arguments against Chevron waiver do not apply so neatly to Skidmore and Auer. For instance, we claim that Chevron waiver contravenes Chenery I’s instruction that courts must review the agency’s justifications for its action—not those of the agency’s lawyers. But most courts already give Skidmore and Auer deference to interpretations advanced for the first time during litigation. See E.I. Du Pont De Nemours & Co v Smiley, 138 S Ct 2563 (2018) (mem) (Gorsuch respecting the denial of certiorari) (questioning whether interpretations advanced during litigation merit Skidmore deference).

Perhaps Chenery I also means that courts shouldn’t give Skidmore or Auer deference to an agency’s brief (as Justice Gorsuch’s statement in Smiley suggests). If so, then the arguments against Chevron waiver apply just as well here. But a conceptual distinction between Chevron, on the one hand, and Skidmore and Auer, on the other, might make some sense of these different rules. Under Chevron, courts defer to administrative interpretations because Congress is presumed to have delegated to the agency the authority to issue binding interpretations of the law; under Skidmore and Auer, by contrast, courts don’t owe legal deference but rather give epistemic deference to the agency’s relative subject-matter expertise. Put differently, under Skidmore and Auer, the court respects the agency’s relative expertise when interpreting the statute or regulation for itself—not because Congress said that it must. This conceptual distinction tracks what Professor Peter Strauss has calledChevron space” and “Skidmore weight.” If Auer and Skidmore are in fact about expertise rather than delegation, the question courts should ask is whether an agency’s waiver of deference undermines its supposed expertise.

This same conceptual distinction might also show why our separation-of-powers arguments against Chevron waiver do not apply to Auer and Skidmore. We argue in our essay that Chevron waiver undermines the separation-of-powers principles that undergird Chevron by altering Congress’s intended allocation of interpretive authority. (In a forthcoming comment, Jeremy Rozansky advances a similar argument that a reasonable Congress would not want courts to allow agencies to waive Chevron.). But if Auer and Skidmore arise as judge-made rules of convenience for reviewing complicated administrative action, then allowing agencies to waive deference doesn’t seem to alter that allocation of interpretive authority. In short, whether the administrative law and separation-of-powers arguments against Chevron waiver apply here turns on how we conceptualize Auer and Skidmore—as rules of legal deference or as useful rules-of-thumb for judges making independent decisions about complicated regulatory regimes.

Whatever the force of these differences between waiving Chevron and waiving Auer and Skidmore, our argument from waiver doctrine still counsels against subjecting Auer and Skidmore deference to ordinary waiver rules. Still, we recognize that special circumstances may sometimes lead courts to decline to address issues relating to Auer and Skidmore, when the parties fail to raise the issue in their briefing; we might think of this exception as a “prudential rule of convenience.” United States v Burke, 504 US 229, 246 (1992) (Scalia concurring in the judgment). By way of illustration, consider the Ninth Circuit’s decision in Pakootas v Teck Cominco Metals, LTD, 830 F3d 975 (9th Cir 2016). There, the court declined to afford Skidmore deference because, according to the court, the agency had waived deference and because doing so would require the court “to determine whether an agency interpretation that is due Skidmore deference but not Chevron deference can trump a previous judicial interpretation, a question left open after Brand X.” Id at 986 n 12. The court sensibly “decline[d] to reach such a complex issue on less than full briefing.” Id.

Thus, in the end, our arguments against Chevron, Auer, and Skidmore waiver represent a change in degree, not of kind. Currently, courts will not address un-briefed issues relating to administrative deference unless they find a special reason to excuse the waiver. Under our approach, by contrast, courts should independently determine whether an administrative deference regimes applies unless they identify a special reason that justifies avoidance. In our view, this approach is more consistent with principles of waiver and independent judicial decision-making.


Both authors graduated from Yale Law School in 2018.