Also known as: FRCP 24 · Fed. R. Civ. P. 24 · Federal Rule of Civil Procedure 24 · intervention · permissive intervention · intervention of right
Written by attorneys · grounded in primary & secondary sources — see below
A federal rule of civil procedure that permits a nonparty to join an existing civil action as a plaintiff or defendant. The rule distinguishes intervention of right, which the court must allow when a statute confers an unconditional right or when the applicant claims an interest relating to the property or transaction that may be impaired by the disposition, from permissive intervention, which the court may grant when the applicant's claim or defense shares a common question of law or fact with the main action. The court must also consider whether intervention will unduly delay or prejudice the original parties.
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After a truck owned by Rocky Mountain Mining collides with a pedestrian, the pedestrian sues the driver for negligence. A third motorist injured in the same collision moves to intervene under Rule 24 to assert her own damages claim against the driver. The court allows the intervention because the third motorist's interest in the accident will be impaired if the original action proceeds without her, and the disposition may bind her rights.
Ridgeway Partners sues Redwood Bank for breach of a loan agreement in federal court under diversity jurisdiction. A supplier with a related payment claim against the bank files a motion to intervene under Rule 24. The court grants intervention because the supplier's claim forms part of the same case or controversy as the original loan dispute.
During an altercation, Rowan Russell steps in to shield Ronald Reed from an attacker. Russell is later sued for assault. He moves to intervene in Reed's separate self-defense action under Rule 24 to assert his own justification. The court permits the intervention because Russell's interest may be impaired by the outcome of the original proceeding.
Rising Sun Electronics sues a contractor for property damage caused by excavation. A neighboring landowner whose fence was also affected moves under Rule 24 to intervene. The court denies the motion as untimely because the normal consequence of the excavation was already foreseeable and the intervention would prejudice the original parties.
Ravi Reddy, a citizen of State A, sues Roger Ramirez, a citizen of State B, in federal court for $100,000. A second plaintiff from State A seeks to intervene under Rule 24 to assert a related claim against Ramirez. The court denies supplemental jurisdiction because the intervention would destroy complete diversity under section 1332.
Rosalind Reed raises her arm toward Ryan Roberts during an argument. Roberts moves to intervene in a related assault action under Rule 24. The court allows intervention because Roberts reasonably believed the raised arm would result in imminent contact absent his defensive action.
Intervention of right requires the court to allow a nonparty to join when a federal statute grants an unconditional right or when the applicant has an interest in property or a transaction that may be impaired by the action. Permissive intervention is discretionary and may be granted when the applicant's claim or defense shares a common question with the main action.
In actions founded solely on diversity jurisdiction, section 1367(b) withholds supplemental jurisdiction over claims by plaintiffs seeking to intervene under Rule 24 when doing so would be inconsistent with the requirements of section 1332. This prevents parties from using intervention to circumvent complete diversity.
…according to his professional judgment up to the points where important state interests provide compelling justifications for intervention. Up to those points, the abortion decision in all its aspects is inherently, and primarily, a medical decision, and basic responsibility for it must rest with the physician. If an…
…enough for advocates of quick, complete change, but majoritarian institutions were listening and acting. Heavy-handed judicial intervention was difficult to justify and appears to have provoked, not resolved, conflict.” Ginsburg, Some Thoughts on Autonomy and Equality in Relation to Roe v. Wade, 63 N. C. L. Rev. 375, 385–386…
…of the properties were willing sellers; and contracts of sale were accordingly consummated. It is clear that but for the active intervention of the state courts, supported by the full panoply of state power, petitioners would have been free to occupy the properties in question without restraint. These are not cases, as has been…
…Article III of the United States Constitution. Such supplemental jurisdiction shall include claims that involve the joinder or intervention
…v. Atlantic Richfield Co. , 435 U. S. 151, 157 (1978), and our reluctance to "believe Congress intended to authorize federal intervention
The motion must be served on the parties under Rule 5 and must state the grounds for intervention. It must also be accompanied by a pleading that sets out the claim or defense for which intervention is sought.
Under Rule 24(b)(3), the court must consider whether the intervention will unduly delay or prejudice the adjudication of the original parties' rights whenever it exercises discretion over a permissive intervention request.