Definition
Materiality is the legal quality of a fact, statement, omission, or breach that makes it significant enough to affect a legal outcome. A matter is material when it has the natural tendency, or is reasonably capable, of influencing the decision, judgment, or result to which it relates. The threshold varies by context, but the core question is always the same: does this matter enough to change something that counts?
Because materiality operates across nearly every field of law, its practical meaning shifts by context:
1. Evidence. A fact is material if it is relevant to a matter at issue in the case — meaning it tends to prove or disprove something the trier of fact must decide. Materiality and relevance are related but distinct; a fact may be relevant without being material if the point it supports is not actually in dispute.
2. Fraud and misrepresentation. A false statement is material if a reasonable person would consider it important in deciding whether to enter a transaction, or if the speaker knew the particular recipient was likely to rely on it. Immaterial misstatements, even if false, generally will not support a fraud claim.
3. Contract law. A breach is material if it defeats the essential purpose of the contract or deprives the non-breaching party of a substantial portion of what they bargained for. Material breach entitles the non-breaching party to suspend performance and pursue remedies; a minor breach does not.
4. Securities law. A fact is material if there is a substantial likelihood that a reasonable investor would consider it important in making an investment decision. This standard, drawn from federal securities regulation, is among the most developed and litigated articulations of the concept.
5. Criminal law and perjury. A false statement in a judicial or official proceeding is material if it could have affected the proceeding's outcome. Immateriality is a defense to perjury.
6. Constitutional and administrative law. Materiality appears in due process contexts (e.g., whether withheld evidence was material to the defense under Brady doctrine), as well as in administrative determinations where the significance of omitted or erroneous information is assessed.
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Common Language
Modern common usage (Wiktionary): The quality of being material; having a physical existence. | The quality of being of consequence to a legal decision.
Historical common usage (Webster's 1913): The quality or state of being material; material existence; corporeity. Importance; as, the materiality of facts.
In ordinary English, "material" often means physical or tangible — corporeal existence. In law, materiality has nothing to do with physical substance. The legal concept tracks the second sense in both sources — consequence, significance, influence on outcome — but legal materiality is not simply "importance" in the colloquial sense. It is a calibrated threshold question: important enough, to this decision, under this legal standard. Researchers encountering the word in historical documents should not assume the author means tangible or physical when writing in a legal context.
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Common Confusion
Materiality is frequently conflated with relevance, but they are not synonymous. Relevance asks whether evidence tends to make a fact more or less probable. Materiality asks whether that fact is actually at issue in the proceeding. In modern Federal Rules of Evidence practice, the two concepts are merged under the single standard of "relevance" (Fed. R. Evid. 401), but historical sources — and many state courts — treat them as separate inquiries. Researchers reading older cases or treatises must recognize that a court rejecting evidence as "immaterial" was making a different objection than one rejecting it as "irrelevant."
Materiality is also sometimes confused with prejudice or weight. A fact can be material (important to an issue) without being highly probative, and probative evidence can be immaterial if the point it supports is undisputed or legally irrelevant.
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Why It Matters in Research
Materiality is one of the most context-dependent terms in legal research. The standard that governs materiality in a securities fraud case is not the same standard that governs it in a perjury prosecution, a contract dispute, or a Brady suppression motion. Researchers who carry one field's materiality standard into another field's analysis will reach wrong answers.
In historical sources, materiality appears most prominently in evidence treatises and pleading manuals, where it tracked the common law distinction between facts in issue (material) and background facts (immaterial). The merger of materiality into relevance in the Federal Rules of Evidence (1975) created a discontinuity: post-1975 federal cases use "relevant" where earlier federal and state cases would have said "material." Researchers working across that boundary must account for the terminological shift.
Securities law materiality has its own dense case law and is sometimes cited across contexts as if it stated a universal standard. It does not. The "reasonable investor" formulation is specific to that regulatory regime and should not be imported wholesale into common law fraud or evidentiary analysis without care.
In criminal law, the relationship between materiality and perjury has generated persistent interpretive disputes about what "affecting the proceeding" actually means — particularly in grand jury contexts where the ultimate charge may differ from the proceeding in which the false statement was made.
The Law Mind corpus connections here are real: materiality in contract breach (contracts_54) is analytically separate from materiality in criminal material support statutes (criminal_253), which in turn sits in tension with First Amendment limits addressed in constitutional_216. These share the word but not the standard.
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Historical Dictionary Support
The historical sources are sparse to the point of near-uselessness on this term as a standalone entry. Both Black's editions punt to the entry for MATERIAL, treating MATERIALITY as merely "the property or character of being material" — definitionally circular and unhelpfully brief. Rapalje & Lawrence similarly redirects, adding only a pair of case citations under the adjacent heading MATERIALS and MATERIALS FOR BUILDING, which are irrelevant to the abstract concept.
Bouvier's is the most useful of the four, offering two distinct propositions: first, that materiality concerns "substantial importance or influence, especially as distinguished from formal requirement"; second, that it means "capability of properly influencing the result of the trial." This two-part framing is historically significant. The contrast with formal requirement captures a recurring theme in common law pleading: a defect is material if it goes to the substance of the claim, not merely to the form in which it was stated. The second proposition — influence on trial result — anticipates the modern perjury and Brady formulations more closely than any of the other sources.
None of the historical dictionaries address materiality's divergent standards across legal contexts, which is where modern legal complexity actually lives.
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Jurisdictional Note
State courts vary considerably in how they define and apply materiality thresholds, particularly in fraud and misrepresentation cases. Some states apply a purely objective reasonable-person standard; others incorporate subjective reliance into the materiality inquiry, blurring materiality with reliance. In evidence law, states that have not adopted the Federal Rules still maintain the traditional relevance-materiality distinction, making that conceptual separation practically important in those jurisdictions.
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Encyclopedia Cross-Reference
contracts_54: Performance — Material Breach vs. Minor Breach (The Law Mind Contracts & Commercial Law Encyclopedia)
criminal_253: Terrorism Offenses and Material Support (18 USC 2339) (The Law Mind Criminal Law Encyclopedia)
constitutional_216: Terrorism, Material Support Statutes, and First Amendment Limits (The Law Mind Constitutional Law Encyclopedia)
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