Definition
Non detinet (Latin: "he does not detain") is the name given to the general issue plea in two related common law forms of action:
1. In detinue: The defendant's general issue plea denying the wrongful detention of the plaintiff's personal property. By pleading non detinet, the defendant denies both that he holds the goods and that he wrongfully withholds them, putting the whole of the plaintiff's claim in issue.
2. In replevin (detention-only): Where a replevin action is grounded solely on wrongful detention rather than on wrongful taking, non detinet serves as the general issue plea. It is not the appropriate plea where the wrongful taking itself is in dispute.
The plea is a formal procedural device of the English common law pleading system, requiring the defendant to respond to the plaintiff's declaration by traversing its central allegation — unlawful detention — in a single comprehensive denial.
Common Confusion
Non detinet is sometimes conflated with non cepit, which is the general issue in replevin actions where the gravamen is wrongful taking rather than wrongful detention. The two pleas are context-specific: non detinet answers to detention; non cepit answers to caption. Using the wrong plea in a replevin action was a pleading defect under strict common law rules. A researcher encountering either term in historical records should first determine which branch of the replevin action — taking or detention — the litigation concerned.
Why It Matters in Research
Non detinet is a term belonging almost entirely to the pre-code era of common law pleading. Researchers will encounter it almost exclusively in English and American cases and treatises predating the abolition of the forms of action — roughly before the mid-nineteenth century in England (the Judicature Acts of 1873–1875) and before the adoption of code pleading in American states (many of which followed New York's Field Code of 1848). After those reforms, detinue and the structured plea system it produced largely disappeared from American practice, absorbed into general civil claims for conversion or replevin under procedural rules that no longer required formal issue-pleading by recognized names.
The dual function of non detinet — serving both detinue and the detention-branch of replevin — is a trap for researchers. A case index or digest entry citing non detinet does not, by itself, tell you which action was brought. You must read the underlying declaration to determine whether the plaintiff sued in detinue (seeking return of specific goods or their value) or in replevin for detention only. The distinction matters because the remedies and procedural histories differ.
Researchers working in Southern state reporters from the nineteenth century will find non detinet in a functional American context, not merely as an English transplant. The second edition of Black's preserves a citation to Berlin Machine Works v. Alabama City Furniture Co., a real Alabama case from 1896, which confirms that formal detinue practice persisted in some American jurisdictions well into the post-Civil War period.
Be alert to the fact that modern legal databases may not index this Latin phrase consistently. Variant spellings and abbreviations appear in older printed reports.
Historical Dictionary Support
All three sources — Black's (1st and 2nd editions) and Burrill — agree on both the translation and the two-context function of the plea: general issue in detinue, and general issue in replevin where detention alone is alleged. The agreement is essentially complete, as would be expected for a term of settled procedural nomenclature.
Burrill's entry, as reproduced here, is truncated, but its substantive content aligns with the Black's formulations. All three sources trace the detinue usage to Tidd's Practice (1 Tidd, Pr. 645) and the replevin usage to Burrill's Practice (2 Burrill, Pr. 14), reflecting that nineteenth-century American legal dictionaries drew from the same small canon of common law practice treatises.
What the historical dictionaries do not address is the procedural consequence of a successful non detinet plea — specifically, how judgment ran, whether the plaintiff could proceed to claim value in the alternative, or how traversal of this issue interacted with subsequent pleading. For that depth, Tidd's Practice and Gould's Treatise on the Principles of Pleading remain the primary period sources.
Jurisdictional Note
Non detinet as a live procedural plea has no meaningful role in modern American or English litigation. England abolished the forms of action through the Judicature Acts; American jurisdictions abolished them serially through code and rules-based pleading reforms. The term retains research relevance only in historical and appellate records from jurisdictions — particularly Southern states — where common law forms of action persisted into the late nineteenth century.