INTERVENOR

3 definitions found across Law Mind sources

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INTERVENORAuthored
The Law Mind • 1089 words
Definition
A person or entity who was not an original party to a lawsuit but who, with leave of the court, joins the proceeding to protect a right or interest affected by the outcome. The intervenor becomes a party to the suit upon admission and may assert claims, defenses, or arguments as authorized by the court or applicable procedural rules. The intervenor's participation is distinct from that of an amicus curiae: an intervenor steps into the litigation as a party with a stake in the result, not merely as an outside voice offering argument. ---
Common Language
Modern common usage (Wiktionary): "One who intervenes, especially in a legal sense." Historical common usage: Webster's 1913 does not provide a distinct entry for intervenor as a common English word; it is effectively a legal term of art that migrated into general vocabulary through its procedural context. The common-language sense captures the surface meaning — someone who steps in — but misses the procedural formality entirely. In legal usage, intervention is not self-executing. The intervenor must seek and obtain court permission (or qualify under a rule granting intervention as of right), making the term inseparable from the procedural framework that creates it. ---
Common Confusion
INTERVENOR vs. AMICUS CURIAE: An amicus curiae ("friend of the court") submits a brief but does not become a party and has no independent right to advance claims or control the litigation. An intervenor acquires party status and the rights that come with it, including the ability to file motions, conduct discovery (in some jurisdictions), and appeal. Researchers encountering either term in older sources should not assume functional equivalence. INTERVENOR vs. THIRD-PARTY DEFENDANT: A third-party defendant is brought into a case involuntarily by an existing defendant asserting a claim against them. An intervenor enters voluntarily, on their own initiative, to protect their own interests. The distinction matters for understanding how and why a non-original party appears in the record. ---
Core Elements
Intervenor status typically requires satisfaction of several conditions, though the specific formulation varies by jurisdiction and era: 1. Non-party status at inception: The intervenor was not named or served in the original action. 2. Leave of court or right by rule: Admission requires either a court order granting permissive intervention or a showing that intervention is available as of right (e.g., where the intervenor's interest may be practically impaired by the proceeding and is not adequately represented by existing parties). 3. Protected interest: The intervenor must assert a cognizable legal or equitable interest in the subject matter of the litigation — not mere curiosity or general concern. 4. Timeliness: Applications to intervene must be timely; courts may deny intervention sought after substantial proceedings have occurred. ---
Why It Matters in Research
The term intervenor appears across a wide range of Law Mind corpus materials — equity practice, admiralty, administrative proceedings, and modern civil procedure — and its meaning is procedurally context-dependent in ways that can trap the unwary researcher. In equity practice (well-represented in older Law Mind sources), intervention was a discretionary equitable remedy, not a codified right. A researcher reading 19th-century chancery records will find "intervenor" used where the modern researcher expects a rule-based analysis; the underlying concept is the same, but the pathway to that status was more ad hoc and court-dependent. In administrative law materials, intervenor carries additional weight: public interest organizations, regulated parties, and government agencies frequently appear as intervenors in agency proceedings, and the term describes a recognized participant category with defined rights under many regulatory frameworks. This usage is analytically distinct from civil litigation intervention. Watch for inconsistency in older sources between intervenor (the person) and intervener (a variant spelling). Both appear in Law Mind historical sources; they are synonymous. The corpus also contains materials from jurisdictions — particularly in admiralty and probate — where intervention procedures differed meaningfully from general civil practice. Do not assume the rules governing an intervenor in one procedural context translate directly to another. ---
Historical Dictionary Support
Bouvier's Law Dictionary defines intervenor as one who, "by leave of the court, interposes in a suit and becomes a party thereto to protect a right or interest in the subject-matter," and separately as "a person who intervenes in a suit, either on his own behalf or on the behalf of the public." The second prong of Bouvier's formulation — intervention on behalf of the public — is worth flagging. It reflects a conception of intervention that extends beyond private interest protection and anticipates the public-interest intervenor familiar in modern administrative and environmental litigation. This aspect of the term's scope is often underemphasized in purely procedural treatments. Bouvier's entry correctly ties intervenor to intervention as its parent concept and offers no independent substantive analysis beyond that link, consistent with the term's essentially relational character: an intervenor is defined entirely by the act and procedural mechanism of intervention. What historical dictionaries do not address — and what became increasingly significant in 20th-century practice — is intervention as of right versus permissive intervention. This distinction, codified in rules like Federal Rule of Civil Procedure 24, is absent from pre-code sources. Researchers using Bouvier's or similar historical authorities should understand that the older sources describe a discretionary, court-controlled mechanism, not the bifurcated right/permission framework that governs most modern practice. ---
Jurisdictional Note
Federal practice under Rule 24 distinguishes sharply between intervention of right and permissive intervention. Many states follow analogous frameworks, but the threshold for intervention of right — particularly what constitutes an "interest" sufficient to trigger it — varies in application across circuits and state courts. Researchers working with materials from specific jurisdictions should verify local procedural rules rather than assuming federal standards apply. ---
Encyclopedia Cross-Reference
Law Mind Encyclopedia — Intervention (Civil Procedure) Law Mind Encyclopedia — Parties (Civil Procedure) Law Mind Encyclopedia — Amicus Curiae ---
Related Terms
Intervention — the procedural act and mechanism by which an intervenor joins a suit; the parent concept Intervener — variant spelling; synonymous Amicus Curiae — related but distinct: participates without acquiring party status Third-Party Defendant — non-original party brought in involuntarilynot by own election Party — the broader status category the intervenor enters upon admission Leave of Court — the permission mechanism required for most intervention Standing — related threshold concept; intervenors must generally demonstrate a cognizable interest analogous to standing requirements Permissive Intervention — the discretionary form of intervention Intervention of Right — the mandatory form where qualifying conditions are met
INTERVENORmain
Bouvier's Law Dictionary • 1928
One not originally a party who, by leave of the court, inter- poses in a suit and becomes a party thereto to protect a right or interest in the subject- matter. A person who intervenes in a suit, either on his own behalf or on the behalf of the public. See INTERVENTION. INTERVENTION (Lat. intervenio, to come between or among). In Practice. The admission, by leave of the court, of a person not an original party to pending legal proceedings, by which such person becomes a party thereto for the protection of some right or interest alleged by him to be affected by such proceedings. Persons who are not parties to a suit cannot in general file a petition therein for a stay of proceedings or any other cause; the remedy is by original bill. Exceptions are: where the pleadings contain scandal against a stranger, or where a stranger pur- chases the subject of litigation pending the suit, and the like; creditors are allowed to prove debts and persons belonging to a class on whose behalf the suit is brought are regarded as quasi parties and, of course, may have a standing in court; per Bradley, J., in 2 Woods 628. Third persons may be driven to intervene for their rights in equity if those rights are to be affected, and if at the hearing the court would be compelled to notice their absence and order the case to stand over until they were brought in; 19 Fed. Rep. 659. See 1 Dan. Ch. Pr. 287 ; Story, Eq. Pl. § 220. It is not necessary to the right of intervention, in order to par- ticipate in a trust fund in the custody of the law, that the intervenor should first obtain judgment at law or should have any lien upon the fund. Intervention will be granted, after a foreclosure decree against a railroad company, to unsecured note- holders who pray to have their debts estab- lished as equitable liens upon the property and funds of the company paramount to the lien of the mortgage; 21 Fed. Rep. 264. A holder of railroad bonds secured by a mortgage under foreclosure has an inter- est in the amount of the trustee's compen- sation, which entitles him to intervene and to contest it and to appeal from an adverse decision; 111 U. S. 684. Where a part of a canal was sold and the fund brought into court, it was held that the contractor who built the canal could intervene for the pro- tection of his rights either upon the fund or against the purchaser; 105 U. S. 509. Bondholders in a foreclosure suit brought by the trustee of the mortgage are quasi parties and may be heard for the protection of their interests; 53 Fed. Rep. 850. If one who is a necessary party to a case in a state court is wrongfully excluded and denied leave to file a proper cross bill and answer and to present a motion for removal to the federal court, he will be treated by the latter court as if a party: 23 Fed. Rep. 356. A case in 8 Fed. Rep. 97 was based on special facts. Where a suit in equity was properly instituted against a railroad company by a stockholder, a bondholder, and the trustees for the bondholders named in the land grant mortgages of the company, and the bill charged that the officers of the com- pany were squandering its property, and the purpose of the suit was the preserva- tion and administration of the assets of the company, and a decree pro confesso had been entered and a receiver appointed, individual stockholders were not permitted to intervene and file a cross bill on a gen- eral charge of fraud and collusion on the part of the receiver and erroneous judg- ment on the part of the court in making the order referred to. In such a suit, it is not the proper practice to allow individual stockholders to intervene to set aside the proceedings or to interpose obstacles to the progress of the suit. Such stockholders may come in to take the benefit of the pro- ceedings and decree, but not to oppose and nullify them. Rival creditors by proceed- ings before the master may fix the priority of their respective liens, and creditors or stockholders may contest the validity of the claims of other creditors and stock- holders, but all in subordination to the general object of the suit, to obtain an ad- ministration of the company's assets and property. Persons will not be allowed to intervene as general defendants unless they show that they have an interest in the results as stockholders, and are also able to show fraud and collusion between the plaintiff in the suit and the officers of the company; per Bradley, J., in 2 Woods 323. In 3 Hughes 320, the Amsterdam Bondholders' Committee, representing a very large num- ber of bonds, filed a petition setting out the grounds for disapproving their trustees' management of the foreclosure suit, and praying intervention, but leave to intervene was denied; 55 Fed. Rep. 448. Where the holder of a large amount of bonds, on which foreclosure proceedings were pending, asked leave to intervene, and it appeared that the mortgage trustee was already a party and there was no allegation that it was not acting prop- erly for
intervenornoun
Wiktionary (English) • 2026
Wiktionary contributors • CC BY-SA 4.0 • via Kaikki
Extracted and formatted for display by Law Mind. Source link opens the current Wiktionary page and its contributor history; it is not a frozen copy of this extract.
One who intervenes, especially in a legal sense.

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