Definition
Threatening letters is the name given to a criminal offense consisting of the sending of written communications that contain threats of the kinds recognized as criminal under the applicable statute. The offense is defined by statute rather than by common law alone, meaning the specific threats that qualify — whether threats to injure a person, to damage property, to accuse someone of a crime, or to extort money — depend on the jurisdiction's legislative text. The act of sending is the operative conduct; the letter need not be received, and the threat need not be carried out, for the offense to be complete.
The term is primarily a label of convenience rather than a term of art with fixed elements across jurisdictions. Modern statutes have largely subsumed it under broader headings such as extortion, harassment, stalking, or terroristic threats.
Common Language
Modern common usage (Wiktionary): A letter written with the intent to frighten, intimidate, or coerce the recipient, often by threatening violence or harm.
Historical common usage (Webster's 1913): Not separately defined; subsumed under general usage of "threat" as a declaration of an intention to inflict harm.
The common and legal meanings are close, but the legal term carries a specific procedural character: it names a statutory offense, not merely a type of communication. A letter that a layperson would call "threatening" may or may not satisfy the statutory definition, which often requires that the threat be of a particular kind (e.g., threat to kill, threat to expose a secret to extort money) and that it be made with criminal intent. The ordinary meaning also does not capture the rule that sending — not receiving — completes the offense.
Common Confusion
Threatening letters is sometimes used interchangeably with extortion by letter or blackmail, but the terms are not identical. Extortion and blackmail require a demand for something of value; a threatening letter may be purely intimidatory with no demand attached. Conversely, some statutes fold threatening-letter conduct into extortion when a demand accompanies the threat. Researchers should check whether the jurisdiction treats these as the same offense or as distinct charges that may be brought together.
Why It Matters in Research
The term's statutory dependence is the central research challenge. Because the offense has no fixed common-law definition, historical sources describing "threatening letters" as a crime are describing whatever the relevant statute prohibited at that time and place — which varied considerably. A New York statute from the mid-nineteenth century (the jurisdictional context of People v. Griffin) would not be a reliable guide to what constituted the offense in another state or under a later federal statute.
Federal law has long addressed threatening communications separately from state law. Researchers working on federal materials should look to statutes governing threats transmitted through the mail or interstate commerce rather than to the generic threatening-letters label.
In historical corpus research, this term tends to appear in indictment forms, criminal practice manuals, and newspaper accounts of prosecutions. It is rarely used in modern criminal codes, which have replaced it with more specific offense names. When reading nineteenth- or early-twentieth-century sources, treat "threatening letters" as a category that points toward the underlying statute rather than as a self-defining offense.
The term also appears in civil contexts — defamation, intentional infliction of emotional distress — where a threatening letter may be both a crime and a tort. Researchers should be alert to this dual character when reading older case materials that discuss the same conduct in both registers.
Historical Dictionary Support
Both editions of Black's Law Dictionary provide the same lean definition: threatening letters is the name of the offense of sending letters containing threats of the kinds recognized by the statute as criminal. The second edition adds a citation to People v. Griffin, 2 Barb. (N.Y.) 429, a mid-nineteenth-century New York case, as illustrative authority.
The circularity of the definition — the offense consists of threats recognized by statute as criminal — reflects the drafters' acknowledgment that the term has no independent content. Black's is not attempting to define the elements; it is identifying the label and deferring to the legislative text. This is useful for researchers to know: looking to Black's for substantive guidance on what threats qualify will not succeed. The dictionary entry functions as a pointer to statutes and cases, not as a source of elements.
Neither edition addresses the federal dimension of the offense, the question of whether receipt is required, or the relationship to extortion and blackmail — gaps that a researcher working in any of those areas must fill from primary sources.
Jurisdictional Note
The offense is wholly statutory and therefore varies significantly by jurisdiction in its elements, required mental state, and penalties. Federal law treats threats transmitted through the mail as a distinct federal offense, independent of state threatening-letters statutes. Researchers should not assume that a case interpreting one state's statute resolves questions under another state's law or under federal provisions.