Definition
A peremptory defense is a defense that defeats the opposing party's claim absolutely and finally, either by showing that the plaintiff never had a valid right to bring the action in the first place, or by showing that any such right, once valid, has since been extinguished. Unlike a dilatory defense — which merely delays or suspends a proceeding without addressing the underlying merits — a peremptory defense strikes at the root of the claim. A successful peremptory defense ends the litigation on the merits, leaving no residual right for the plaintiff to reassert.
The concept operates at two distinct levels:
1. No right ever existed. The defendant contends that the plaintiff's asserted right was legally invalid from the outset — that the cause of action was never cognizable, that a required condition precedent was never met, or that some legal bar (such as lack of standing or incapacity) prevented the suit from arising at all.
2. Right extinguished. The defendant concedes, or does not contest, that a right once existed but argues it has since been terminated — by release, accord and satisfaction, statute of limitations, merger, payment, or similar extinguishing event.
Common Confusion
PEREMPTORY DEFENSE vs. DILATORY DEFENSE. These two categories are frequently encountered together in historical pleading texts, and the distinction matters for research. A dilatory defense — such as a plea in abatement — challenges the form, timing, or forum of an action without denying its underlying merit, and leaves the plaintiff free to recommence a properly framed suit. A peremptory defense is terminal: it bars the claim itself. The word "peremptory" in this context shares its root meaning with the peremptory challenge in jury selection (final, absolute, brooking no contest), but the two uses are procedurally distinct and should not be conflated.
PEREMPTORY DEFENSE vs. AFFIRMATIVE DEFENSE. Modern procedural codes use the term "affirmative defense" (as in Federal Rule of Civil Procedure 8(c)) where older common-law pleading used "peremptory defense." The concepts substantially overlap — both introduce new matter that defeats the claim — but they are not synonymous. Not all affirmative defenses are peremptory in the classical sense; some operate only to limit, reduce, or delay a remedy rather than extinguish the cause of action entirely.
Why It Matters in Research
The term "peremptory defense" belongs primarily to the vocabulary of common-law pleading, and researchers will encounter it most heavily in sources predating the merger of law and equity under modern procedural codes (mid-nineteenth century onward in most U.S. jurisdictions; 1938 federally under the Federal Rules of Civil Procedure). After that merger, the term largely disappeared from American procedural writing, replaced by "affirmative defense."
In historical sources, expect the term to appear in treatises on common-law pleading — Chitty, Gould, and Stephen on pleading are the canonical authorities — as well as in equity practice manuals. When reading nineteenth-century case law or pleading opinions, the peremptory/dilatory distinction was outcome-determinative: courts treated dilatory pleas with suspicion and required strict compliance with form, while peremptory defenses were evaluated on their substantive merits.
Researchers working with modern materials who encounter "peremptory defense" should treat it as a signal that the source was written in, or is quoting from, a common-law pleading framework. Mapping it onto modern Rule 8(c) affirmative defenses is usually appropriate but requires care — verify whether the specific defense at issue operates to extinguish the claim entirely or merely to limit relief.
Be alert to loose usage: some older state court opinions use "peremptory defense" informally to mean any complete defense, without invoking the technical pleading distinction. Context governs.
Historical Dictionary Support
Black's Law Dictionary transmits the definition through Bouvier's Institutes (4 Bouv. Inst. no. 4206), the foundational American treatise source for common-law pleading terminology. Bouvier's framing — that a peremptory defense either negates the original right or shows its extinguishment — is the standard formulation and reflects the position in English pleading practice carried into American law.
The historical sources are consistent on the core meaning. Where they are less helpful is in charting how the term aged out of active use. Neither Black's nor Bouvier's flags the displacement of this vocabulary by code pleading and, later, by the Federal Rules. Researchers relying solely on historical dictionary entries may not realize that a concept described in present tense in an 1891 Black's edition is largely a historical artifact in modern federal practice.
Jurisdictional Note
A handful of states retaining older procedural codes or strong common-law pleading traditions — notably in some Southern states through the mid-twentieth century — continued using the peremptory/dilatory classification longer than the federal courts. Researchers in state court historical records should check whether the relevant jurisdiction had adopted code pleading and when.
Encyclopedia Cross-Reference
The Law Mind Criminal Law Encyclopedia, Jury Selection — Voir Dire, Peremptory Challenges, and Batson (criminal_181) — for the distinct but terminologically related use of "peremptory" in the jury challenge context.