Definition
Interdiction carries two distinct legal meanings that share only the underlying concept of prohibition or restraint.
1. Civil/Personal Interdiction. A judicial proceeding and the resulting decree by which a person — typically one found to be of unsound mind, in a state of habitual imbecility, or otherwise incapable of managing their own affairs — is stripped of legal capacity and placed under the administration of a guardian or curator. The interdicted person (the interdit) cannot independently enter contracts, convey property, borrow money, receive payment, or take legal action without the involvement of a court-appointed adviser or guardian. The decree must ordinarily be served on the person, recorded, and posted publicly. Interdiction is the civil law and French law analog to what common law systems accomplish through incompetency adjudication and plenary guardianship.
2. Commercial/International Interdiction. A governmental prohibition on commercial intercourse between the citizens or subjects of one country and those of another specified country or port. A commercial interdiction, when total, means a complete cessation of trade and exchange between the designated parties — not a mere restriction or regulation of it. This is distinct from a tariff, embargo, or partial trade restriction.
Common Language
Modern common usage (Wiktionary): The act of interdicting or something interdicted; also the military destruction of an enemy's supply lines or forces before they can be used.
Historical common usage (Webster's 1913): The act of interdicting; prohibition; a prohibiting decree; a curse or interdict.
The gap between common and legal usage is real but directional rather than contradictory. Ordinary English captures the broad prohibitory sense, and military usage has given "interdiction" a specific tactical meaning (cutting off supply routes) that has no legal analog. Legal usage narrows the term into two technical channels — one governing personal legal capacity, the other governing commercial relations between states — neither of which maps neatly onto the everyday or military sense.
Common Confusion
Personal interdiction is frequently conflated with guardianship or conservatorship. The distinction matters for researchers: interdiction is the proceeding and the status, not the arrangement for ongoing administration. A person under interdiction has lost civil capacity by judicial decree; the guardian or curator is a separate legal actor appointed to fill that gap. In common law jurisdictions, the equivalent proceedings are called incompetency determinations, committee appointments, or conservatorships depending on the era and jurisdiction — the word "interdiction" will not appear in those records even when the legal result is the same.
Commercial interdiction is sometimes used interchangeably with "embargo" in historical sources, but the terms are not synonymous. An embargo typically suspends a country's own ships or goods from departure or entry; an interdiction of commercial intercourse prohibits exchange itself, targeting the transaction rather than the vessel or cargo.
Recognized Forms
/SUBTYPES
Full interdiction: Total deprivation of legal capacity, requiring a guardian or curator for all civil acts.
Partial or limited interdiction: In the French and Louisiana civil law traditions, a court may stop short of full interdiction and instead require that the person obtain counsel appointed by the court before taking specific legal actions (borrowing, compromising claims, conveying property). This partial form is a distinct status with narrower consequences.
Commercial interdiction: Prohibition of trade and exchange with a named country or port, typically enacted by statute or executive proclamation.
Why It Matters in Research
Jurisdictional displacement is the central research trap. Personal interdiction is primarily a civil law concept — developed in French law and transplanted into Louisiana, Quebec, and other civilian jurisdictions. Researchers working in common law records (English, federal, or most U.S. state materials before the twentieth century) will rarely encounter the word "interdiction" in the personal-capacity sense. When it does appear in common law sources, it is usually comparative commentary or borrowed terminology. Conversely, researchers in Louisiana materials will find interdiction proceedings in court records as the standard mechanism for incapacity adjudication — not guardianship or conservatorship.
For commercial interdiction, the critical research moment is the early American republic. The Non-Intercourse Act of 1809 (the act of March 1, 1809) produced a body of federal litigation that defined what "interdiction" of commercial intercourse means in American law — specifically, that it signifies total cessation, not partial restriction. Cases arising from that act and from the Embargo Acts of the Jefferson administration are essential primary sources for this meaning.
The two meanings rarely appear in the same corpus. Researchers should identify at the outset which sense is operative in their sources, because search terms, finding aids, and secondary literature are organized differently around each.
Historical sources inconsistently describe the procedural steps of personal interdiction — particularly the appellate stages and the distinction between full and partial interdiction. Bouvier's coverage is more procedurally granular than Black's on this point.
Historical Dictionary Support
The historical dictionaries largely agree on the existence of two separate meanings but differ in emphasis and depth.
Black's Law Dictionary (both first and second editions) leads with the civil law and French law personal-capacity meaning, providing a workable definition of the interdit's status and the guardian's role. Both editions truncate their coverage, however, and do not address the procedural architecture of interdiction proceedings or the distinction between full and partial interdiction.
Bouvier's Law Dictionary is more comprehensive on both fronts. On commercial interdiction, Bouvier ties the term directly to American statutory history and the Supreme Court's interpretation of the 1809 Non-Intercourse Act — the most instructive historical source on the commercial meaning in American law. On personal interdiction, Bouvier describes the procedural consequences of a rejected application (partial interdiction with required counsel), the public posting and recording requirements, and the appellate process. This procedural detail is absent from Black's.
Rapalje & Lawrence addresses the French law meaning briefly in the context of persons over twenty-one in a habitual state of imbecility or insanity, framing it accurately as exclusion from legal capacity. The entry is compact and comparative rather than analytical.
None of the historical dictionaries adequately address Louisiana's interdiction jurisprudence as a developed American civilian system, nor do they flag the divergence between the common law incompetency framework and the civil law interdiction framework for researchers who need to move between the two.
Jurisdictional Note
Personal interdiction in its technical sense is operative primarily in Louisiana (and historically in Quebec and other civil law jurisdictions). Louisiana's Civil Code carries interdiction provisions that differ materially from the guardianship statutes of common law states. Researchers applying common law incompetency doctrine to Louisiana sources, or vice versa, risk misreading both the procedural record and the legal consequences.
Encyclopedia Cross-Reference
See Law Mind Encyclopedia — Guardianship and Incompetency (for personal interdiction in civil and common law systems); Embargo and Commercial Interdiction (for the commercial prohibition meaning and its statutory history in American law).