Rule 50 Noncompliance Waives Sufficiency-of-the-Evidence Review on Appeal—No Plain-Error Backstop

Case: Nelson v. Toyota Motor Corporation, No. 24-1408 (10th Cir. June 1, 2026) (Order and Judgment, nonprecedential except for law of the case, res judicata, and collateral estoppel)

1. Introduction

This Tenth Circuit decision arises from a diversity products-liability trial in the District of Colorado. Plaintiff-Appellant Wesley Nelson (through his conservator) sued Toyota Motor Corporation on a single theory: strict liability based on an alleged manufacturing defect in a Toyota RAV4. After a two-week trial, the jury found the vehicle did not have a manufacturing defect that rendered it unreasonably dangerous.

On appeal, Mr. Nelson sought to “overturn” the jury verdict solely on the ground that the evidence was insufficient. The central issue became procedural: whether Mr. Nelson preserved any sufficiency-of-the-evidence challenge for appellate review given his failure to comply with the two-step mechanism of Federal Rule of Civil Procedure 50.

2. Summary of the Opinion

The Tenth Circuit affirmed the judgment for Toyota without reaching the evidentiary merits. It held that Mr. Nelson’s failure to move for judgment as a matter of law under Rule 50(a) and then renew that challenge under Rule 50(b) foreclosed appellate review of the sufficiency of the evidence. The panel also rejected Mr. Nelson’s attempt to obtain plain-error review, explaining that post-Unitherm Food Systems, Inc. v. Swift-Eckrich, Inc., unpreserved sufficiency claims are treated as waived and not reviewable at all.

3. Analysis

3.1. Precedents Cited

The decision is primarily a preservation and appellate-power opinion. The panel situates its ruling in a line of Supreme Court and Tenth Circuit cases that make Rule 50 compliance a prerequisite to appellate sufficiency review.

A. Background and substantive-law context (strict products liability)

• Pratt v. Petelin, 733 F.3d 1006 (10th Cir. 2013): cited for the appellate lens on facts—reciting “the evidence in the light most favorable to the verdict.” Although the appeal turns on preservation, this citation signals the court’s readiness to apply the ordinary sufficiency framework if properly invoked.
• Oja v. Howmedica, Inc., 111 F.3d 782 (10th Cir. 1997), and Camacho v. Honda Motor Co., 741 P.2d 1240 (Colo. 1987): used to identify Colorado’s strict-liability defect categories (manufacturing, design, warning). These authorities frame the claim type but do not drive the disposition.

B. The Rule 50 preservation architecture in the Tenth Circuit

• ClearOne Commc'ns, Inc. v. Biamp Sys., 653 F.3d 1163 (10th Cir. 2011), and Meyer v. Christie, 634 F.3d 1152 (10th Cir. 2011): cited for the principle that sufficiency review is available only when the challenge was raised in a proper Rule 50(a) motion.
• Helmer v. Goodyear Tire & Rubber Co., 828 F.3d 1195 (10th Cir. 2016): clarifies that appellate courts review the district court’s Rule 50 decisions (i.e., the procedural vehicle is integral to the standard of review).
• Kellogg v. Energy Safety Servs. Inc., 544 F.3d 1121 (10th Cir. 2008), and Rural Water Dist. No. 4, Douglas Cnty., Kan. v. City of Eudora, Kan., 659 F.3d 969 (10th Cir. 2011): invoked for the “two-step” requirement—preverdict Rule 50(a) and postverdict Rule 50(b)—and for the consequence that failure “precludes our review.”
• U.S. ex rel. MMS Constr. & Paving, L.L.C. v. W. Sur. Co., 754 F.3d 1194 (10th Cir. 2014): reinforces that relief cannot be granted on a ground not presented in a Rule 50(b) motion, highlighting that even partial Rule 50 practice can be insufficient if the specific sufficiency theory was not properly renewed.
• Kelley v. City of Albuquerque, 542 F.3d 802 (10th Cir. 2008); Elm Ridge Expl. Co., LLC v. Engle, 721 F.3d 1199 (10th Cir. 2013); Mountain Dudes v. Split Rock Holdings, Inc., 946 F.3d 1122 (10th Cir. 2019); and Morgan v. Baker Hughes Inc., 947 F.3d 1251 (10th Cir. 2020): cited as consistent Tenth Circuit applications of the post-Unitherm regime: Rule 50 noncompliance “forecloses” sufficiency review.

C. The Supreme Court’s “powerlessness” line: Unitherm and its progeny

• Unitherm Food Systems, Inc. v. Swift-Eckrich, Inc., 546 U.S. 394 (2006): the controlling authority. The panel reads Unitherm as holding a Rule 50(b) motion is a “necessary” prerequisite, and absent it, there is “no basis for review” of a sufficiency challenge. The court emphasizes Unitherm’s rationale that the trial judge, having “the feel of the case,” must be asked first.
• Cone v. W. Va. Pulp & Paper Co., 330 U.S. 212 (1947): supplies the justification for requiring postverdict trial-court judgment before appellate intervention.
• Ortiz v. Jordan, 562 U.S. 180 (2011): quoted for the statement that, without Rule 50(b), an appellate court is “powerless” to review sufficiency after trial.
• Dupree v. Younger, 598 U.S. 729 (2023): relied on for the broad proposition that a party must raise a sufficiency-of-the-evidence claim in a post-trial motion to preserve it for appeal.

D. The now-abrogated Tenth Circuit approach and why plain error is unavailable

• Cummings v. Gen. Motors Corp., 365 F.3d 944 (10th Cir. 2004): discussed as pre-Unitherm law that allowed sufficiency challenges without Rule 50(b) (so long as Rule 50(a) was filed), with plain-error review for nonrenewal. The panel underscores that Unitherm abrogated this approach.

E. Waiver vs. forfeiture; appellee preservation defenses; and a cautious claim-processing detour

• Richison v. Ernest Grp., Inc., 634 F.3d 1123 (10th Cir. 2011): cited for the general idea that forfeited theories may be reviewed for plain error, then contrasted with Rule 50’s waiver-like effect.
• Johnson v. Spencer, 950 F.3d 680 (10th Cir. 2020), and United States v. McGehee, 672 F.3d 860 (10th Cir. 2012): used to address whether Toyota adequately invoked the lack-of-preservation defense and to justify giving Toyota “credit” despite some briefing “mixed messages.”
• Kontrick v. Ryan, 540 U.S. 443 (2004); Eberhart v. United States, 546 U.S. 12 (2005); United States v. Mitchell, 518 F.3d 740 (10th Cir. 2008); and McIntosh v. United States, 601 U.S. 330 (2024): cited to explain the distinction between jurisdictional rules and claim-processing rules, and that claim-processing rules may be waived/forfeited by litigants. The court expressly avoids deciding whether Rule 50 is jurisdictional or claim-processing, holding it unnecessary because Toyota sufficiently invoked the preservation problem.
• Malouf v. Sec. & Exch. Comm'n, 933 F.3d 1248 (10th Cir. 2019): cited as an example of deciding a case without resolving whether a requirement is jurisdictional or claim-processing where it must be enforced either way.

F. “Doubly doomed” and cross-circuit reinforcement

• Cavanaugh v. Woods Cross City, 718 F.3d 1244 (10th Cir. 2013), and Green Constr. Co. v. Kan. Power & Light Co., 1 F.3d 1005 (10th Cir. 1993): cited for the proposition that failing to move under Rule 50(a) independently precludes sufficiency review.
• Jackson v. Esser, 105 F.4th 948 (7th Cir. 2024): quoted for the phrase “doubly doom[ed]” where both Rule 50(a) and 50(b) are missing.
• Wiener v. AXA Equitable Life Ins. Co., 153 F.4th 413 (4th Cir. 2025): cited for the broader federal consensus that sufficiency appeals require a Rule 50(b) motion.

G. The panel’s internal-circuit housekeeping: addressing contrary signals

• Brothers v. Johnson, 105 F.4th 1279 (10th Cir. 2024): discussed as potentially implying plain-error review might exist for unpreserved sufficiency challenges. The panel treats any such suggestion as dictum because Brothers also stated Unitherm “foreclosed” relief.
• United States v. Villarreal-Ortiz, 553 F.3d 1326 (10th Cir. 2009) (per curiam); Patrick G. ex rel. Stephanie G. v. Harrison Sch. Dist. No. 2, 40 F.4th 1186 (10th Cir. 2022); Tokoph v. United States, 774 F.3d 1300 (10th Cir. 2014); and Bay v. Anadarko E&P Onshore LLC, 73 F.4th 1207 (10th Cir. 2023): used to define and operationalize dictum versus holding.
• United States v. Rosales-Miranda, 755 F.3d 1253 (10th Cir. 2014); Haynes v. Williams, 88 F.3d 898 (10th Cir. 1996); Auraria Student Hous. at the Regency, LLC v. Campus Vill. Apartments, LLC, 843 F.3d 1225 (10th Cir. 2016); and King of the Mountain Sports, Inc. v. Chrysler Corp., 185 F.3d 1084 (10th Cir. 1999): invoked for the intra-circuit conflict rule requiring adherence to earlier settled precedent if tension exists.

3.2. Legal Reasoning

The court’s reasoning proceeds in four moves:

1. Rule 50 is the exclusive procedural gateway for sufficiency challenges after a civil jury trial: appellate “de novo” sufficiency review is, more precisely, review of the district court’s Rule 50 rulings, and those rulings do not exist unless the litigant made the required motions.
2. Unitherm renders the requirement categorical: the absence of a Rule 50(b) motion deprives the appellate court of a basis—and, in Unitherm’s terms, “power”—to review sufficiency.
3. Mr. Nelson failed both steps: he made no Rule 50(a) motion at any point and filed no Rule 50(b) motion (and no Rule 59 motion). The panel treats this as independently fatal under both Rule 50(a) doctrine (no preverdict notice) and Rule 50(b) doctrine (no postverdict renewal).
4. Plain-error review is unavailable for this category of omission in the Tenth Circuit post-Unitherm: the court characterizes Rule 50 noncompliance as “waiver,” not mere forfeiture, and anchors that characterization in decades of circuit practice. It also neutralizes any contrary implication from Brothers v. Johnson by labeling it dictum (or, alternatively, superseded by earlier precedent).

3.3. Impact

Although labeled “not binding precedent,” the opinion consolidates several practical and doctrinal consequences for civil trial practice:

• Trial lawyers must calendar Rule 50 as appellate insurance. A litigant who intends to argue “insufficient evidence” must (i) file a targeted Rule 50(a) motion before submission to the jury and (ii) file a corresponding Rule 50(b) motion after an adverse verdict. Trying the case “hard” is not preservation.
• No “plain-error parachute” in the Tenth Circuit for unpreserved sufficiency claims. The panel’s extended treatment of waiver/forfeiture is a warning that appellate courts will not repackage sufficiency as plain error when Rule 50 steps are missing.
• Appellees should explicitly invoke Rule 50 preservation. The decision models a generous (but not limitless) approach to whether an appellee adequately raised preservation defenses; still, appellees are better served by citing Unitherm directly and clearly characterizing the defect as waiver.
• Products-liability merits remain untouched. For Colorado strict-liability manufacturing defect litigation, the “impact” is indirect: dispositive procedural defaults can end the appeal irrespective of technical defect evidence (e.g., airbags/pretensioners not deploying).

4. Complex Concepts Simplified

• Judgment as a matter of law (JMOL): A request that the judge decide an issue because no reasonable jury could lawfully find otherwise on the evidence presented.
• Rule 50(a) vs. Rule 50(b): Rule 50(a) is the preverdict JMOL motion (before the case goes to the jury). Rule 50(b) is the postverdict “renewed” JMOL motion (after the jury verdict), which must track arguments raised under 50(a).
• Why the postverdict motion matters: The trial judge—having observed witnesses and trial dynamics—must be given first opportunity to decide whether the verdict lacks evidentiary support or whether a new trial is warranted.
• Waiver vs. forfeiture: Forfeiture is a failure to timely assert a right (sometimes reviewed for “plain error”). Waiver is the intentional or rule-based relinquishment that bars appellate review altogether. This opinion treats missing Rule 50 steps as waiver-like.
• Claim-processing vs. jurisdictional rules: Jurisdictional rules cannot be waived and must be enforced by courts at any time. Claim-processing rules generally must be enforced when properly invoked by the opposing party and can be forfeited if not timely raised. The panel assumes (without deciding) Rule 50 could be claim-processing, but enforces it because Toyota adequately invoked the defect.
• “Nonprecedential” decisions: This order and judgment is not binding precedent for future panels, but it can be cited for persuasive value and binds the parties through doctrines like law of the case, res judicata, and collateral estoppel.

5. Conclusion

Nelson v. Toyota Motor Corporation is a procedural reaffirmation: in the Tenth Circuit, a party cannot obtain appellate review of the sufficiency of the evidence supporting (or undermining) a civil jury verdict unless the party complied with Rule 50’s two-step process—preverdict Rule 50(a) and postverdict Rule 50(b). The opinion’s most consequential message is practical: without Rule 50 motions, even potentially strong sufficiency arguments are nonstarters on appeal, and plain-error review does not revive them.