Also known as: FRCP 23 · Fed. R. Civ. P. 23 · Rule 23 · Federal Rules of Civil Procedure 23
Written by attorneys · grounded in primary & secondary sources — see below
A federal procedural rule that authorizes class actions when the prerequisites of numerosity, commonality, typicality, and adequacy are met and one of the three categories in subdivision (b) is satisfied. The rule supplies the standards for certification, notice, and judgment binding effect in federal court. Under the Rules Enabling Act it governs class certification in diversity actions even when a conflicting state statute would bar class treatment.
Faith Fitzgerald sues Fairfield Bank on behalf of thousands of depositors alleging the bank delayed crediting daily interest. The court finds her claims typical of the class and that she will fairly protect absent members interests. Because separate suits would risk inconsistent standards of conduct for the bank, the action proceeds as a class under Rule 23(b)(1).
Felicia Fuentes files a diversity class action against Fulton Shipping seeking only statutory interest on late payments. A state statute bars class actions for such interest claims. The court applies Rule 23 instead because the federal rule is valid under the Rules Enabling Act and displaces the conflicting state restriction.
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Nora Nguyen sues National Motors on behalf of 1,200 purchasers alleging a common defect in vehicle braking systems. The court finds the class so numerous that joinder is impracticable and that common questions of defect and warranty predominate. Certification is granted under Rule 23(a) and (b)(3).
Oscar Ortiz represents a class of employees seeking an injunction against a company-wide promotion policy alleged to discriminate on the basis of race. The court finds the defendant acted on grounds applicable to the class as a whole. Certification proceeds under Rule 23(b)(2).
Paula Patel sues a pharmaceutical firm on behalf of patients harmed by a recalled drug. The court examines whether counsel is qualified and whether Patel's interests conflict with absent class members. Finding no conflicts, the court certifies the class under Rule 23(a)(4).
Quinn Quinn represents policyholders challenging an insurer's denial of claims. After certification under Rule 23(b)(3) and proper notice, the final judgment binds all class members who did not opt out. The court relies on Rule 23(c)(3) to define the judgment's preclusive scope.
No. When Rule 23 directly addresses whether an action may proceed as a class and is valid under the Rules Enabling Act, it governs and displaces the conflicting state statute. The federal rule regulates procedure without altering substantive rights to interest or recovery.
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The court first asks whether a Federal Rule directly answers the procedural question. If Rule 23 is on point and valid because it regulates practice or procedure without abridging substantive rights, it controls even if the state rule would produce a different outcome.
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Yes. Rule 23 sets the uniform federal standards for class certification. Because the rule is procedural and does not change the underlying substantive claims or remedies, it displaces contrary state procedural limitations in federal court.
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…when Cohen arose can appreciate the strong state policy reflected in the statute. I think it wholly legitimate to view Federal Rule 23 as not purporting to deal with the problem. But even had the Federal Rules purported to do so, and in so doing provided a substantially less effective deterrent to strike suits, I think the…