Definition
A prochronism is a chronological error in which a date assigned to an event, document, or instrument is earlier than the date on which that event actually occurred. In legal contexts, the term applies most directly to written instruments — deeds, contracts, wills, notes, or court filings — that bear a date preceding the moment of their actual execution or entry. The error may be inadvertent (a scrivener's mistake, a misdated notarization) or intentional (an attempt to establish priority, satisfy a deadline, or avoid a legal consequence).
Prochronism is the mirror image of postdating. Where postdating assigns a future date to a present act, prochronism assigns a past date — whether by mistake or design.
Common Language
Modern common usage (Wiktionary): An error in chronological order in which something is ascribed an earlier time than the actual one.
Historical common usage (Webster's 1913): The dating of an event before the time it happened; an antedating; opposed to metachronism.
The common and legal meanings are essentially identical in substance, but the legal meaning carries consequences that the general definition does not imply. In ordinary usage, prochronism is a neutral descriptive term for any anachronism running backward. In legal usage, the same act — depending on intent — may constitute fraud, void an instrument, defeat a priority claim, or trigger perjury liability where a date is sworn to.
Common Confusion
Prochronism is easily conflated with antedating, and the two terms are often used interchangeably in legal sources. The distinction, where one is observed, is that antedating is the deliberate act of assigning an earlier date, while prochronism may encompass both inadvertent and intentional misdating in the earlier direction. Neither term should be confused with postdating (assigning a future date) or metachronism (assigning a later date than the actual one). Researchers encountering any of these terms in historical sources should not assume consistent usage — older legal writers frequently used antedating and prochronism without differentiation.
Why It Matters in Research
Prochronism is a rare technical term in the Law Mind corpus, but it surfaces in two distinct research contexts that are worth distinguishing.
First, in disputes over instrument priority — recording acts, lien priority, contract formation — the question of whether a document was executed when it claims to have been executed is substantive, not merely technical. A deed recorded with a false execution date may defeat a later purchaser's claim or manufacture apparent compliance with a statute of limitations. Researchers tracing priority disputes in older equity cases may find the term prochronism used where modern opinions would say antedating or fraudulent dating.
Second, in historical document authentication and probate litigation, prochronism appears in arguments attacking the genuineness of wills, deeds, and correspondence. Courts examining whether a will was executed before or after a testator lost capacity, or whether a conveyance predated a judgment lien, are addressing prochronism even when they do not use the word.
Trap for researchers: because prochronism is not a term of art in modern American practice, it will rarely appear in post-twentieth-century case law. Searches using only this term will miss the relevant modern doctrine, which travels under fraud, antedating, backdating, or false dating. Conversely, searching historical equity reports and English chancery materials for antedating will surface cases that period writers described as prochronism.
The term is also relevant to notarial law. A notary who certifies an acknowledgment with a date earlier than the actual acknowledgment has committed a prochronism; depending on jurisdiction and intent, this may void the instrument or expose the notary to license consequences.
Historical Dictionary Support
Black's Law Dictionary, both the first and second editions, define prochronism identically: "An error in chronology; dating a thing before it happened." This definition is notable for two reasons. First, it frames prochronism as an error — a neutral characterization that does not distinguish innocent mistake from deliberate fraud. Second, it is among the shorter entries in both editions, suggesting that the editors treated it as a technical vocabulary term worth defining for completeness rather than a term requiring doctrinal elaboration.
Webster's 1913 adds the useful gloss that prochronism is "opposed to metachronism," providing the conceptual pair that legal dictionaries omit. Neither edition of Black's supplies this counterpart, which leaves researchers without a natural pointer to the opposing error (assigning a date later than actual). The historical legal dictionaries offer no case illustrations, no discussion of fraudulent intent, and no jurisdictional context — gaps that make them useful for identifying the term but insufficient for understanding its legal consequences.
Jurisdictional Note
No American jurisdiction uses prochronism as a formal term of art in its statutes or procedural rules. The operative legal concept — misdating a document to an earlier date — is addressed through fraud doctrine, forgery statutes, and notarial law, which vary by state. Researchers working in civil law jurisdictions may find the concept more explicitly treated in notarial codes, where dating requirements for authentic instruments are strictly governed.