The action of debt is the oldest personal common law action. The field of the action of debt is broader than that of pure contract law and lies to enforce a legal duty created by contract, custom or record. There was, however, one great restriction upon the scope of this action, which was that the duty, which was the basis of the action, must be for the payment of a certain sum of money or for the delivery of a certain amount of ponderable or measurable chattels. In very early times, the action of debt was even broader than this, being used in action for the recovery of a specific article. An action of debt for this last purpose was known as an action of debt in the de-tinet, while other actions of debt were known as actions of debt in the debet et detinet. Actions of debt in the detinet soon branched off from this action and gave rise to the new action of detinue.

"Evidences of the proprietary character of the action of debt are conspicuous throughout all its history, but this feature is more prominent in the early stages of its growth. It is plainly manifest in the wording of the early writ. The creditor complained that the debtor unjustly deforced him of the subject-matter of the debt, and the debtor was commanded that justly and without delay he render it to its owner. By the time of Bracton the word detains (detinet) had supplanted the word deforce as descriptive of the wrongful exclusion of the owner from his property. As in the writ of right for land, the action was based on ownership; and the writ of debt has been aptly called the 'writ of right for money.' The analogy between debt and the proprietary action for land is shown in the further circumstance that in both there might be trial by battle; but the offer of proof by battle has not actually been found in actions of debt.

"The proprietary character of the action being much more plainly marked in the detinet form of the action, it is not surprising to find that while the simple duty to pay a debt was originally conceived as an obligation so purely personal as to perish with the person, the duty to pay chattels did not so perish. Accordingly when the debtor died, the writ, in order to be maintainable, always had to be framed in the detinet solely, whether the debt was for money or chattels."1

Debt was used in suits on sealed instruments, for penalties named in a lease2 for a fine due under custom,3 in suits on judgments,4 for the recovery of rent, and on rights of a quasi-contractional character.5 At common law the right of action for debt, except in cases of surety, was personal and transitory. It would not lie against a personal representative to recover a debt due from the estate of a deceased person, but would lie against the heir where the specialty evidencing the debt expressly binds the heir, and where the heir has funds.

The two causes which brought about the disuse of the action of debt were the necessity of proving the claim to the exact amount alleged, and the fact that the defendant had the right of "wager of law."

1 Street's Foundations of Legal Liabilty, Vol. III, p. 130-131. 2 Cibel vs. Hill, 1 Leon, 110.

3 Y. B., 11, Hen. VII, 13, pl. 8.

4 Y. B., 43 Edw. III., 2, pl 5.

5 Speake vs. Richards, Hob. 206, pl. 260.

By the time that the wager of law was abolished, assumpsit had occupied the field formerly possessed by debt.