Also known as: FRCP 24 · Fed. R. Civ. P. 24 · Rule 24
Written by attorneys · grounded in primary & secondary sources — see below
A procedural rule that permits nonparties to join an existing federal civil action. On timely motion the court must allow intervention when the applicant claims an interest relating to the property or transaction that is the subject of the action and is so situated that disposing of the action may as a practical matter impair or impede the applicant's ability to protect that interest unless existing parties adequately represent the interest.
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Pinnacle Ed, a State A corporation, sued Southern University in federal court under diversity jurisdiction for unpaid license fees. Malcolm, a State B resident, moved under Rule 24 to intervene as a plaintiff and assert tuition-refund claims against Summit University, a State B corporation joined as a third-party defendant. Because Malcolm and Summit share citizenship, the court lacks supplemental jurisdiction over the intervenor's claims.
Minority applicants denied admission to the University of Michigan law school sued the university over its race-conscious admissions policy. Proposed defendant-intervenors who supported the policy moved to intervene as of right, claiming their educational opportunities would be impaired if the policy were struck down. The court granted intervention because the applicants' interests were not adequately represented by the university.
Leah sued Atlantic Securities for securities fraud arising from a bond offering. Ridge Equity, which had issued insurance on the same bonds, moved under Rule 24 to intervene as of right, asserting that an adverse finding on the disclosures would practically impair its coverage defenses in parallel state actions. The court denied intervention because Atlantic Securities adequately represented the shared interest in defending the disclosures.
Female employees sued their employer for sex discrimination and obtained a consent decree with race- and gender-conscious remedies. Male employees moved under Rule 24 to intervene, claiming the decree impaired their promotion opportunities. The court permitted intervention because the existing parties did not represent the male employees' distinct interests.
A class of female employees obtained a consent decree altering promotion practices. Male firefighters moved under Rule 24 to intervene after judgment, asserting that the decree impaired their seniority rights. The court allowed intervention because the motion was timely for purposes of appeal and the existing parties did not represent the male firefighters' interests.
The government defended a campaign-finance statute against constitutional challenge. Political parties and candidates moved under Rule 24 to intervene as defendants, claiming that invalidation of the statute would impair their competitive position in upcoming elections. The court permitted intervention because the government did not adequately represent the intervenors' distinct electoral interests.
The elements are timeliness, an interest relating to the property or transaction, practical impairment of the ability to protect that interest, and inadequate representation by existing parties. All four must be satisfied for mandatory intervention.
Supporting sources
Section 1367(b) bars supplemental jurisdiction in diversity-only cases over claims by persons seeking to intervene as plaintiffs under Rule 24 when exercising jurisdiction would be inconsistent with the complete-diversity requirements of section 1332.
…claims by persons proposed to be joined as plaintiffs under Rule 19 of such rules, or seeking to intervene as plaintiffs under Rule 24 of such rules, when exercising supplemental jurisdiction over such claims would be inconsistent with the jurisdictional requirements of section 1332." All parties to this litigation and…
…Opinion of Judge Daughtrey Before us are two cases in which proposed defendant-intervenors were denied intervention under Federal Rule of Civil Procedure 24(a) and (b), in actions brought against the University of Michigan contesting the use of an applicant's race as a factor in determining admission. The appeals come from separate district…
…be "typical of the claims or defenses of the class." The words "claims or defenses" in this contextjust as in the context of Rule 24
…on the question whether respondents may sue their state employers for damages under Title II of the ADA, see this Court's
…judgment may be entered on behalf of the plaintiff. See § 502.64(b);
Supporting sources
No. When a federal statute grants only a conditional right to intervene, the court may permit intervention under Rule 24(b)(1)(A) without requiring the applicant to prove impairment or inadequate representation.
Supporting sources
Practical impairment focuses on whether disposition of the action may as a practical matter limit the applicant's ability to protect its interest even without binding preclusion. Persuasive effect in later proceedings can satisfy the element when the interest is concrete.
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