Definition
A Latin term meaning "indebted." In legal usage, indebitatus appears almost exclusively as the foundation of the phrase indebitatus assumpsit — a common law form of action in which a plaintiff alleged that the defendant, being indebted to the plaintiff, had (expressly or by legal implication) promised to pay. The term also appears in the plea nunquam indebitatus ("never indebted"), the defendant's responsive pleading denying the existence of the underlying debt.
As a standalone word, indebitatus carried no independent procedural significance. Its meaning is almost entirely bound to the two formulas in which it functioned.
Common Confusion
INDEBITATUS ASSUMPSIT vs. SPECIAL ASSUMPSIT: These are two branches of the same action of assumpsit, and historical sources sometimes treat them interchangeably, which creates confusion. Indebitatus assumpsit (also called general assumpsit) was used to recover a liquidated debt or a sum certain — the promise to pay was implied by law from the fact of the debt. Special assumpsit, by contrast, was grounded in an express promise and was used where the plaintiff needed to prove the actual agreement rather than rely on a legal fiction of promise. The distinction mattered acutely in pleading because the available counts, the required averments, and the applicable pleas differed between the two forms.
INDEBITATUS ASSUMPSIT vs. DEBT (the action): Before assumpsit expanded to cover money claims, the writ of debt was the primary vehicle for recovering a sum certain. Indebitatus assumpsit eventually displaced the action of debt in many circumstances because assumpsit allowed trial by jury under more favorable conditions and avoided the wager of law. Researchers encountering money claims in early common law records must determine which form was used, as the procedural record will look quite different.
NUNQUAM INDEBITATUS vs. NIL DEBET: These are successive generations of the same plea. Nil debet ("he owes nothing") was the older general denial in the action of debt. When indebitatus assumpsit displaced debt as the preferred form of action, English practice substituted nunquam indebitatus ("never indebted") as the corresponding general denial. The two pleas serve the same function but belong to different procedural eras.
Why It Matters in Research
Researchers will almost never encounter indebitatus as an isolated term. It appears in corpus materials as a component of longer Latin phrases, and its significance depends entirely on which phrase is involved.
For indebitatus assumpsit: This is one of the most important concepts in the history of common law pleading and quasi-contract. Its development tracks the creative expansion of the action of assumpsit from the 16th century onward, and understanding it is prerequisite to reading any common law pleading record involving money claims before the procedural reforms of the 19th century. The common counts — for money lent, money had and received, goods sold and delivered, quantum meruit, quantum valebat — were all vehicles within indebitatus assumpsit. When a historical source references any of these common counts, indebitatus assumpsit is the governing framework.
The procedural shift from debt to indebitatus assumpsit was gradual and contested, and the transition period generates inconsistent usage across sources. Documents from the 16th and early 17th centuries may reflect hybrid or transitional practice. Researchers should not assume that a money claim labeled "assumpsit" in a historical record was necessarily a true indebitatus assumpsit rather than a special assumpsit — the specific count matters.
For nunquam indebitatus: Because this plea replaced nil debet at a specific moment in English procedural history, its presence in a pleading record is a rough dating signal. Records deploying nil debet are operating under the older debt framework; records deploying nunquam indebitatus reflect the assumpsit era. This can help researchers place undated or ambiguously dated materials within the correct procedural framework.
American colonial and early republic materials complicate the picture further. American courts did not uniformly or simultaneously adopt English procedural reforms, so the timing of the nil debet / nunquam indebitatus transition varies by colony and then by state. Do not assume English timing applies to American records.
Historical Dictionary Support
The historical dictionaries agree on the core definition — "indebted" — and on the significance of nunquam indebitatus as a replacement plea. Black's (both editions) and Burrill converge precisely on this point. Anderson directs the reader to assumpsit without elaboration, which is practically useful but contributes nothing to understanding indebitatus itself.
Black's 2nd edition provides the most substantive entry, beginning the definition of indebitatus assumpsit before the text breaks off mid-sentence ("he promised"). This truncation is a known feature of the edition and is not an error in the source material — researchers relying on the 2nd edition for a complete account of indebitatus assumpsit will need to supplement it with treatise sources. The 1st edition is more compressed but complete on the plea.
What the historical dictionaries collectively underemphasize is the doctrinal importance of indebitatus assumpsit as the ancestor of modern quasi-contract and unjust enrichment law. The "money had and received" count within indebitatus assumpsit became the primary vehicle through which courts imposed liability where no true contract existed, laying groundwork for restitutionary recovery that persists in modern law under different terminology.