Definition
To hinder, obstruct, or preclude an act, event, or outcome from occurring. In legal usage, "prevent" carries a stronger, more purposive sense than mere obstruction — it implies an affirmative act or omission that stops something from happening, whether or not physical force is involved. The term appears across contract law, criminal law, statutory construction, and civil procedure, and its precise weight in any given context depends on how the surrounding instrument or statute frames the standard of conduct.
In contract law, the concept of prevention is foundational: a party who prevents the other party's performance may not then rely on non-performance as a breach or condition failure. This is sometimes called the prevention doctrine or the prevention principle.
In statutory and regulatory contexts, "prevent" often defines the scope of a duty or prohibition — what a party was required to stop, or what conduct triggers liability for failure to act.
Common Language
Modern common usage (Wiktionary): To stop an outcome; to keep someone from doing something.
Historical common usage (Webster's 1913): In earlier English, "prevent" carried the now-obsolete sense of to go before, to precede, or to anticipate — meaning to act in advance of something rather than to block it. The King James Bible and the Book of Common Prayer use it in this older sense: "We which are alive shall not prevent them which are asleep" means shall not precede them, not shall not stop them.
The gap matters because legal texts written before the mid-nineteenth century may use "prevent" in this archaic sense of anticipation or precedence rather than obstruction. A researcher reading an early equity case or ecclesiastical document that turns on the word "prevent" should not assume the modern meaning applies. Black's 2nd Ed. and Bouvier both define the term in its modern obstructive sense without flagging the historical reversal — a notable omission in sources that otherwise trace Latin roots.
Common Confusion
PREVENT vs. PRECLUDE: These are often used interchangeably in legal writing, but they carry different connotations. "Prevent" suggests an affirmative act of interference with something that could otherwise occur. "Preclude" often signals that a legal rule, finding, or prior proceeding has foreclosed an option as a matter of law — res judicata precludes a claim; a party prevents performance. The distinction matters most in contract and procedural contexts where the mechanism of obstruction determines the legal consequence.
PREVENT vs. HINDER: Bouvier draws an implicit distinction by listing "prevent," "hinder," and "obstruct" as near-synonyms, but they are not always equivalent. Courts have occasionally found that a duty to "prevent" requires more complete intervention than a duty merely to "hinder" — suggesting degrees of obstruction that can affect liability analysis.
Why It Matters in Research
The prevention doctrine in contract law is the primary legal context where this term acquires independent doctrinal weight, and researchers should approach it carefully in historical sources. The doctrine — that a party cannot take advantage of a condition that their own conduct prevented from occurring — appears throughout nineteenth- and twentieth-century contract cases but is often stated as a principle without being labeled "the prevention doctrine." In historical reporters, you may find it embedded in discussion of conditions precedent, excuse, or waiver without "prevent" appearing as a term of art.
For corpus researchers, the critical trap is the semantic shift described above. Pre-1850 materials that use "prevent" in the sense of anticipate or precede will read as legally incoherent if the researcher applies the modern meaning. This is not merely an academic concern — the older sense survived in formal legal and liturgical prose well into periods covered by the Law Mind corpus.
The Bouvier entry is particularly useful because it preserves the civil law meaning of PREVENTION (prevenire) as a jurisdictional concept: the right of a judge to take cognizance of an action over which concurrent jurisdiction exists with another judge. This meaning is entirely separate from the common-law obstruction sense and appears in Louisiana and other civil law-influenced jurisdictions. Researchers working in civil law materials or early American jurisdictions with mixed legal traditions should treat "prevention" in that procedural sense as a distinct term requiring separate analysis.
In statutory construction, courts have occasionally had to decide whether "prevent" in a regulatory mandate requires proof of intentional interference or whether negligent failure to act suffices. That interpretive question recurs in employment law, environmental law, and health and safety regulation — contexts where the Law Mind corpus contains substantial material.
Historical Dictionary Support
All three historical sources agree on the core definition: to hinder, obstruct, or intercept. Black's 1st and 2nd Editions track Webster directly on the primary definition. Black's 2nd Ed. adds case support from federal and state courts to confirm the standard reading. Bouvier is the most analytically useful of the three because it does two things the Black's entries do not: it notes that "prevent" has been held not to require physical force (citing 17 Q.B. 145), and it separately develops PREVENTION as a civil law jurisdictional term.
None of the three historical sources address the archaic English meaning of "prevent" as precedence or anticipation — a significant gap for a dictionary corpus that researchers may rely upon when construing older texts. That omission is understandable given the dictionaries' practical orientation, but it means the historical sources should not be treated as complete guides to the term's meaning in documents predating approximately 1800.
The case citations in Black's 2nd Ed. (including U.S. v. Souders and Green v. State) suggest the term was being litigated in criminal and civil contexts by the late nineteenth century, though the entries do not elaborate on what those disputes involved.
Jurisdictional Note
The civil law sense of "prevention" as a doctrine of concurrent jurisdiction — where the judge first seizing cognizance of a matter excludes other judges with equal authority — remains relevant in Louisiana and in comparative law research. This meaning is entirely absent from Black's entries and will not be found by searching common-law sources. Researchers working across the Louisiana corpus should treat PREVENTION (civil law) as a separate lookup from the common-law obstruction sense.
Encyclopedia Cross-Reference
Performance — Prevention, Hindrance, and Failure to Cooperate (The Law Mind Contracts & Commercial Law Encyclopedia)
Breach — Excuse of Conditions (Prevention, Waiver, Estoppel, Forfeiture) (The Law Mind Contracts & Commercial Law Encyclopedia)
Health Insurance Coverage Mandates — Mental Health Parity, Maternity, and Preventive Services (The Law Mind Health Law & Bioethics Encyclopedia)