Definition
Mutually repugnant or contradictory; said of two things that cannot both stand at the same time, such that accepting or establishing one necessarily implies the abrogation or abandonment of the other. The term operates across multiple legal contexts:
1. Inconsistent defenses: Two or more affirmative defenses pleaded in the same action that cannot both be true simultaneously — for example, asserting that the defendant was not present at the scene and, alternatively, that the act was committed in self-defense.
2. Inconsistent statements: A prior statement by a witness that contradicts the witness's current testimony, usable to impeach credibility or, under certain rules, as substantive evidence.
3. Inconsistent laws or provisions: A later enactment or provision that conflicts with an earlier one to the degree that both cannot operate; used in repeal-by-implication analysis and in savings clauses of the form "all laws inconsistent herewith are hereby repealed."
4. Inconsistent conduct or positions: Behavior or legal positions taken by a party that are so at odds with a current claim as to support estoppel or waiver arguments.
---
Common Language
Modern common usage (Wiktionary): Not compatible with another thing; lacking internal consistency; self-contradicting; not coherent in thought or behavior.
Historical common usage (Webster's 1913): Irreconcilable; discordant; not exhibiting uniformity of sentiment or steadiness of principle; unequal; fickle; changeable.
The common and legal meanings are closely aligned at the core — both signal that two things cannot coexist without contradiction. The legal difference lies in consequence: in law, inconsistency is not merely a logical observation but a trigger for specific procedural and substantive outcomes, including impeachment, implied repeal, estoppel, or dismissal. The common meaning carries no such weight.
---
Common Confusion
INCONSISTENT vs. INCOMPATIBLE vs. REPUGNANT: These three terms are often used interchangeably in older legal texts and sometimes in modern opinions. Anderson's directs readers to all three as near-synonyms. In practice, repugnant tends to appear in real property and contract contexts (particularly regarding deed conditions or contract clauses that directly conflict with one another), while incompatible appears more often in constitutional and statutory construction analysis. Inconsistent is the broadest of the three and is the dominant term in evidence and civil procedure contexts. Researchers should not assume these terms carry identical legal weight across all contexts simply because historical dictionaries treat them as equivalents.
---
Why It Matters in Research
The term inconsistent does significant work in at least three distinct areas of the Law Mind corpus, and conflating them causes research errors.
In evidence law, inconsistent is a term of art governed by specific procedural rules. The distinction between a prior inconsistent statement used only for impeachment and one admitted as substantive evidence turns on whether it was made under oath at a prior proceeding — a distinction Black's 2nd Ed. does not address, reflecting how evidence doctrine evolved well after that edition was published. Researchers working in the modern evidence context must look beyond historical dictionaries entirely on this point.
In statutory interpretation, the phrase "all laws inconsistent herewith" appears in thousands of repealing clauses and savings clauses. Courts have developed specific tests for when inconsistency rises to the level of implied repeal — mere tension between statutes is generally not enough. Historical sources use the term without that doctrinal nuance.
In pleading, the permissibility of inconsistent defenses has shifted over time. Under common law pleading, inconsistent defenses were generally problematic. Under modern notice pleading regimes, alternative and even contradictory defenses are explicitly permitted. A researcher using Black's 2nd Ed. on this point without accounting for that procedural shift will draw incorrect conclusions.
Flag for corpus researchers: Anderson's entry for INCONSISTENT is functionally a redirect — it provides no independent definition, only cross-references to CONDITION, INCOMPATIBLE, and REPUGNANT. That structure signals that Anderson treated the term as purely relational rather than as a standalone concept.
---
Historical Dictionary Support
Black's 2nd Ed. offers a clean, durable core definition: mutually repugnant or contradictory, such that both things cannot stand simultaneously. The formulation is still serviceable and tracks modern usage. Black's illustrates the concept with two applications — inconsistent defenses and statutory repeal clauses — which remain the two most practically important uses today.
Anderson's adds no independent definition, directing researchers instead to cognate terms. This approach is consistent with Anderson's general method for relational or adjectival terms, but it means Anderson contributes no independent analytical weight here. Its cross-references to INCOMPATIBLE and REPUGNANT are the useful takeaway.
Neither historical source addresses the evidence law dimension — prior inconsistent statements, impeachment, and the substantive/impeachment distinction — because those doctrinal structures developed primarily through twentieth-century codification of evidence rules. This is the largest gap between the historical dictionary record and modern legal usage of the term.
---
Jurisdictional Note
The evidentiary treatment of prior inconsistent statements varies by jurisdiction. Federal courts apply the Federal Rules of Evidence, under which a prior inconsistent statement made under oath at a prior proceeding may be admitted as substantive evidence, not merely for impeachment. State courts vary considerably; some track the federal rule, others limit such statements to impeachment use only. Researchers working with state court materials should verify the applicable evidence code before drawing conclusions from federal authorities.
---
Encyclopedia Cross-Reference
civpro_176: Impeachment by Prior Inconsistent Statement — Rule 613 (The Law Mind Civil Procedure & Evidence Encyclopedia)
civpro_182: Prior Statements of Witnesses — Rule 801(d)(1) (Inconsistent, Consistent, Identification) (The Law Mind Civil Procedure & Evidence Encyclopedia)
---