Definition
A threatening letter is a written communication sent to another person containing language designed to frighten, intimidate, or coerce — typically to extort money, compel an act, or cause fear of bodily harm, property damage, or some other injury. The term operates in two overlapping legal contexts:
1. Criminal law: The sending of a threatening letter is a criminal offense under both common law and modern statutory frameworks. At common law, sending threatening letters for the purpose of extorting money or other valuables was treated as a misdemeanor. Modern statutes have expanded and codified this, creating distinct offenses for threats transmitted in writing, including by mail, with penalties that vary based on the nature of the threatened harm and the purpose behind it.
2. Evidence and tort law: A threatening letter may also serve as documentary evidence in civil proceedings — for harassment, stalking, intentional infliction of emotional distress, or as a predicate act in civil RICO claims. The physical document and its transmission are both relevant.
The criminal analysis turns on two key questions: the content and character of the threat, and the intent of the sender. Most frameworks do not require that the recipient actually experience fear, but the threat must be of a kind objectively capable of inducing fear in a reasonable person.
Common Confusion
The term is sometimes used loosely to describe any hostile or aggressive communication — including demand letters from attorneys, cease-and-desist letters, or letters asserting legal rights under penalty of litigation. These are not threatening letters in the criminal or tortious sense. A letter warning of legal consequences for a debt, breach of contract, or infringement is protected conduct and generally falls outside the scope of any criminal threatening statute. The distinction lies in whether the threatened harm is unlawful. Threatening to sue is not criminal threat; threatening to harm someone unless paid is.
Why It Matters in Research
Historical sources frame the offense narrowly — focusing almost entirely on extortionate purpose. Researchers working with pre-twentieth-century materials should not assume that threatening letters without an extortion element were treated as criminal. The common law misdemeanor was specifically tied to coercing money or property; threatening letters sent for other purposes (to intimidate a witness, to terrorize a neighbor, to threaten political figures) were addressed piecemeal through other doctrines or not at all.
Modern federal and state statutes have dramatically expanded the offense. In the United States, mailing threatening communications is a federal crime under 18 U.S.C. § 876, which covers letters threatening injury to persons or property. Researchers must distinguish the federal mail-based offense from state-level threatening or harassment statutes, which may not require the postal element and may define the offense differently.
The objective test matters: Bouvier records the principle that the threat must be of a nature calculated to overcome a firm and prudent man — a reasonable person standard focused on the general character of the threat, not the particular vulnerability of the recipient. This standard persists in modified form in modern case law but has been complicated by Supreme Court treatment of the subjective intent question in cases involving true threats under the First Amendment. Researchers working on First Amendment boundaries of threat statutes should be aware that the objective/subjective divide is actively contested doctrine.
For corpus researchers: threatening letter cases intersect with extortion, blackmail, harassment, and stalking in ways that require careful attention to charged offense versus underlying conduct. The same letter may be evidence in multiple proceedings with different legal standards applying in each.
Historical Dictionary Support
Bouvier's treatment is concise and doctrine-light, citing Blackstone's Commentaries (4 Bl. Com. 126) for the common law misdemeanor and an early English criminal case for the reasonable-person standard on the nature of the threat. The entry establishes that the offense is grounded in extortion — the threat is criminal because it is a means of coercing money, not simply because it frightens. Bouvier does not address threatening letters sent without an extortionate purpose, reflecting the narrower common law scope.
The citation to 1 Den. Cr. Cas. 51 is notable: it draws the critical analytical line between the general nature of the evil threatened (objective, evaluated on its face) and the actual psychological effect on the recipient (irrelevant). This distinction between objective threat character and subjective recipient impact is a durable feature of the doctrine.
Historical sources are uniformly thin on what counts as a sufficient threat — they assume the content speaks for itself. Modern researchers should not expect historical dictionaries to resolve ambiguous cases; that work is done by case law.
Jurisdictional Note
Federal law reaches threatening letters transmitted through the mail or interstate communications systems. State statutes vary considerably in whether they require the threat to be written, whether they require proof of intent to cause fear, and whether they include an extortion element as distinct from a standalone threatening communication offense. Some states treat written threats more seriously than verbal ones; others treat them identically. Researchers should identify the charged statute and jurisdiction before applying any general definition.