Predominance in Product-Defect Classes

Yes-or-No in One Stroke: Commonality and Predominance After Speerly

The en banc Sixth Circuit vacated certification of 26 statewide subclasses of GM transmission owners and rebuilt the circuit’s certification law on the way out. "Rule 23 demands that the court conduct a structured two-step approach to assess commonality and predominance." Step one is Rule 23(a)(2): a question "must (1) yield a common answer with common evidence and (2) meaningfully progress the lawsuit," and the decisionmaker "must be able to resolve the question with ‘a yes-or-no answer for the class in one stroke’" — "[i]f a reasonable decisionmaker left with the evidence may answer ‘yes’ to a question for some class members and ‘no’ for others, the class has not shown that it is common" Speerly v. General Motors, LLC, 143 F.4th 306 (6th Cir. 2025) (en banc). The analysis is element-oriented: the court "must walk through each cause of action" and "identify the relevant elements," and it cannot "accept [allegations] as true or construe [evidence] in anyone’s favor." Nor can the hard questions wait — the district court "may—indeed, must—answer merits questions that bear on Rule 23’s demands" and "must not defer merits questions bearing on commonality and predominance until summary judgment," because Rule 23’s text "tells the court to refuse certification until it is assured that certification is proper." At step two, predominance is evaluated "within, not across," each statewide subclass, and "even a slight variation in state law—say, a reliance requirement—might markedly increase the ‘difficulties in managing [the] class.’"

The framework enforces a standard the Supreme Court set fifteen years ago. Wal-Mart Stores, Inc. v. Dukes, 564 U.S. 338 (2011) requires that class claims "depend upon a common contention of such a nature that it is capable of classwide resolution—which means that determination of its truth or falsity will resolve an issue that is central to the validity of each one of the claims in one stroke." What matters "is not the raising of common ‘questions’—even in droves—but, rather the capacity of a classwide proceeding to generate common answers apt to drive the resolution of the litigation," and "[d]issimilarities within the proposed class are what have the potential to impede the generation of common answers." Because "Rule 23 does not set forth a mere pleading standard," certification is proper only if "the trial court is satisfied, after a rigorous analysis, that the prerequisites of Rule 23(a) have been satisfied" — and "[f]requently that ‘rigorous analysis’ will entail some overlap with the merits of the plaintiff’s underlying claim." Speerly makes the lineage explicit: "it flows from Wal-Mart that only an element-oriented analysis permits the court to identify which questions meaningfully move the lawsuit forward."

The first applications mark the doctrine’s edges. In re Humana, Inc., No. 25-502 (6th Cir. Dec 30, 2025) — a Rule 23(f) challenge to a certified TCPA wrong-number class — credited the defendant’s reading that Speerly forbids certifying a class "based on preliminary data showing its potential membership, with plans to later ‘cull the class members’ who, based on individualized evidence, turn out not to have been harmed": "Humana’s characterization of Speerly is correct, insofar as we explained that a district court ‘must not defer merits questions bearing on commonality and predominance until summary judgment’ because, under Rule 23, a court must ‘refuse certification until it is assured that certification is proper.’" But the panel denied review anyway, because "the facts (and reasoning) on which our holding in Speerly relied render that case inapposite" where a single federal claim replaces Speerly’s 26-state patchwork. District courts are running the full sequence: Wade v. Newport Group, Inc., No. 1:22-cv-01126 (W.D. Tenn. Jan 2, 2026) put "the common issues on one side, the individual issues on the other," to "qualitatively evaluate which side predominates," and demanded a damages model that "accounts for how each claim works." Commonality was met on all eight plan-looting tort claims, but for most of them "Rule 23(b)(3) cannot authorize treating [plan participants] as members of a single class" because the aggregate damages model did not match the liability theories — only civil conspiracy was certified, where joint-and-several liability, under which "each conspirator is liable for the damages resulting from the wrongful acts of all co-conspirators in carrying out the common scheme," fit the model.

For plaintiffs, Speerly makes the trial plan the certification motion: walk each claim, each state, and each element, show which elements resolve yes-or-no on common evidence, and tie the damages model to each theory of liability rather than a single aggregate figure. Multistate consumer classes now carry a heavy load in the Sixth Circuit — even one state’s reliance or manifestation requirement can sink a subclass — so narrower single-state or single-statute classes, like the TCPA class that survived in Humana, are where certification still moves. For defendants, the certification fight is now the merits fight: courts may not promise to cull uninjured members later, so every state-law variation, individualized defense, and mismatch between the damages model and the claims belongs in the opposition brief, not held back for summary judgment.