Definition
A letters of caption was a writ issued in Scots law at the instance of a creditor, commanding an officer to seize and imprison the debtor until the debt was satisfied. It functioned as a civil process of arrest, authorizing detention of a person as a mechanism to compel payment of an outstanding obligation. The writ is now obsolete.
Why It Matters in Research
Researchers encountering this term in historical Scots law materials should understand that letters of caption belonged to a broader system of diligence — the Scots law term for debt enforcement — that operated quite differently from English common law remedies. Imprisonment for debt was a recognized enforcement tool in Scots civil procedure well into the nineteenth century before statutory reform curtailed and eventually abolished it.
The term appears almost exclusively in pre-modern sources. If you encounter it in a historical document, it signals a Scots law context; the equivalent English common law process of arresting a debtor's person was accomplished through different writs (capias ad satisfaciendum being the closest analogue). Conflating Scottish diligence procedures with English writs of execution will produce research errors.
Bouvier's cross-reference to "CAP" points toward the broader family of capias writs — writs of taking or arrest — which exist across both common law and civil law traditions. Researchers tracing the conceptual lineage of civil imprisonment for debt should consult both the capias family in English sources and the diligence regime in Scots sources as parallel but distinct threads.
Because the term is obsolete and jurisdiction-specific, it surfaces primarily in: (1) historical Scots legal proceedings and court records; (2) nineteenth-century law dictionaries and encyclopedias cataloging then-current or recently lapsed procedure; and (3) comparative legal histories of debt enforcement and debtor's prison reform. It will not appear in modern practice materials.
Historical Dictionary Support
Bouvier's is the principal anglophone law dictionary source for this term, and its entry is brief by design — the writ was already marked obsolete by the time Bouvier's editors incorporated it, citing the Century Dictionary as their authority. This chain of citation (Bouvier's citing the Cent. Dict.) suggests the term had already passed from active legal use into historical record by the late nineteenth century.
No substantive definition appears in Black's Law Dictionary entries available for cross-check, which is consistent with the term's narrow Scots law application and obsolescence. Researchers should not expect robust treatment in English-language legal dictionaries beyond acknowledgment of the writ's existence.
The brevity of the historical record here is itself informative: letters of caption did not generate a body of common law doctrine or interpretive case law the way English writs did. It was a procedural instrument, and its history is procedural history — best pursued in Scots institutional writers such as Erskine and Bell, and in the legislative history of Scottish debt enforcement reform.
Jurisdictional Note
Letters of caption is exclusively a Scots law term. It has no direct counterpart in English common law, American law, or other common law jurisdictions. Researchers working in any non-Scottish legal context who encounter this term are dealing with either a historical Scots document or a comparative legal reference.