Also known as:class actions · class-action · class-action lawsuit
Written by attorneys · grounded in primary & secondary sources — see below
A procedural device that permits one or more representative parties to litigate claims on behalf of a larger group of similarly situated persons when the requirements of numerosity, commonality, typicality, and adequacy are met. The device aggregates claims that would otherwise require separate actions and produces a judgment binding on all class members who have not opted out.
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Cases
Statutes
Federal Rules
Restatements
Casebooks
Hornbooks
How it applies
Common Examples
6
Inconsistent Adjudications Risk
Cameron Cruz and other borrowers each hold identical loan agreements with Continental Bank that contain the same interest-calculation clause. If every borrower sued separately, some courts might order the bank to apply one interest method while others ordered a different method, leaving the bank unable to comply with all judgments at once. The court therefore certifies the suit as a class action so that a single ruling governs the bank's conduct toward the entire group.
Federal Rule Controls Over State Bar
Caleb Chang, a New York resident, sues an insurer in federal court under diversity jurisdiction seeking statutory interest on late-paid claims. A New York statute would bar class treatment for such penalty claims, but the federal court applies Rule 23 and certifies the class. The certification proceeds because the federal rule governs the procedural question of class availability.
Public Nuisance Representative Suit
Clifford Cox owns land near a factory whose emissions affect an entire neighborhood. He sues the factory for public nuisance and seeks an injunction on behalf of all residents who share the same interference with the public right to clean air. The court permits the suit to proceed as a class action because Cox satisfies the standing requirements for a representative action.
Predominance and Superiority Finding
Christine Castro and thousands of other customers each paid a small overcharge on identical service contracts from Coastal Shipping. Common questions about the contract language and billing practice predominate over any individual damages calculations. The court certifies the class under Rule 23(b)(3) because a single class proceeding is superior to thousands of separate small-claims suits.
School Segregation Class Suit
Craig Caldwell and other African-American schoolchildren in Topeka attend schools segregated by race under state law. They sue the local board of education on behalf of all similarly situated children seeking an order ending the segregation. The suit proceeds as a class action because the constitutional claim is common to every member of the defined class.
Brown v. Board of Education [*Brown I*]347 U.S. 483, 74 S. Ct. 686, 98 L. Ed. 873 (1954)
Marriage Ban Representative Suit
Cassandra Cooper and other interracial couples in Virginia are denied marriage licenses solely because of their race. They file suit requesting a declaration that the ban is unconstitutional. The court resolves the equal-protection claim because it applies uniformly to persons subject to the statutory prohibition.
Loving v. Virginia388 U.S. 1 (1967)
Common questions
Frequently Asked
4
What must a plaintiff show to obtain class certification under Rule 23?+
A plaintiff must satisfy the four prerequisites in Rule 23(a) and at least one category in Rule 23(b). The prerequisites are numerosity, commonality, typicality, and adequacy of representation. The plaintiff must also show that common questions predominate and that a class action is superior when proceeding under subdivision (b)(3).
Does a state procedural rule that bars class actions for certain claims displace Rule 23 in federal court?+
No. When a state rule would deny class treatment, Rule 23 still governs because it is a valid procedural rule under the Rules Enabling Act. The federal rule controls and displaces the conflicting state limitation.
When may a private plaintiff sue for public nuisance as a class representative?
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A private plaintiff may sue as a class representative when the defendant has interfered with a right common to the public and the plaintiff satisfies the standing requirements of Restatement (Second) of Torts § 821C(2)(c). The plaintiff must either show special injury different in kind from the general public or proceed under an authorized representative mechanism such as a class action.
How does the class action device affect subject-matter jurisdiction in diversity cases?+
In traditional diversity cases only the named representative must satisfy the amount-in-controversy requirement. Unnamed members' separate claims are not aggregated. Under the Class Action Fairness Act the claims of all class members are aggregated to determine whether the $5,000,000 threshold is met.
Supporting sources
against Teleprompter in 1976 on behalf of all owners of real property in the State on which Teleprompter has placed CATV components, alleging that Teleprompter's installation was a trespass…
is whether a § 1 complaint can survive a motion to dismiss when it alleges that major telecommunications providers engaged in certain parallel conduct unfavorable to competition, absent…
EvidenceRelevancy and reasons for excluding relevant evidence · Expert testimonyUBEIntermediate