Definition
Per vadium is a Latin phrase meaning "by gage" or "by pledge." It appears in old common law writs—specifically the writs of attachment and pone—as a technical formula indicating the procedural basis on which a defendant was summoned or compelled to appear. The phrase identified that the defendant's appearance was secured through a pledge or surety (a gage), rather than through direct seizure of person or property.
In practice, per vadium denoted the operative clause in these writs that directed the sheriff to attach the defendant by sureties who would guarantee appearance, as distinguished from attachment by direct seizure. Over time, as Latin writs fell into disuse, per vadium was carried forward as the name of that specific clause, translated into English in modern precedents, but functionally the term belongs entirely to the extinct vocabulary of pre-reform common law pleading and process.
Common Confusion
Per vadium is easily conflated with per plegium, another old writ formula also involving pledges or sureties. The distinction is procedural: per vadium refers to the gage or pledge securing a defendant's appearance under a writ of attachment or pone, while per plegium typically appears in replevin proceedings as the pledges given to secure the return of distrained goods. Both terms inhabit the same archaic procedural world, but they arise in different writ contexts and should not be used interchangeably in historical research.
Why It Matters in Research
Per vadium is a navigational term for researchers working in pre-19th-century English common law records, writ registers, and procedural histories. Its significance is almost entirely historical: the phrase survives in legal dictionaries and commentaries not because it has ongoing doctrinal life, but because it helps decode the structure of old Latin writs that appear in original court records, register of writs compilations, and early treatises.
Several traps await the researcher:
First, per vadium never migrated into American common law with any independent doctrinal meaning. Researchers encountering it in American sources will find it only in dictionaries or in treatises that trace English writ procedure historically.
Second, the phrase appears embedded within longer writ formulas. Burrill notes that per vadium was eventually used as the name of the clause itself in modern precedents—meaning that later sources may reference "the per vadium clause" without reproducing the Latin, which can create apparent discontinuities when tracing a procedural concept across sources.
Third, the companion maxim Per varios actus legem experientia facit ("By various acts experience frames the law," attributed to Coke's Institutes) appears in Black's immediately following the per vadium entry. Researchers scanning dictionary pages should not conflate this maxim with the procedural term; the juxtaposition is alphabetical, not conceptual.
For corpus researchers, per vadium is most likely to surface in: Blackstone's Commentaries (Book III), the Registrum Omnium Brevium (Register of Writs), Coke's Institutes, and in American treatises on common law pleading that survey English procedural history. It does not appear as operative language in American statutory or case law with any frequency.
Historical Dictionary Support
All three source dictionaries are in close agreement on the core definition: per vadium means "by gage," appearing in old writs of attachment or pone. Black's (both editions) and Burrill each anchor the definition to Blackstone's Commentaries (Book III, page 280), providing a consistent primary reference point.
Burrill adds a useful procedural note that Black's lacks: per vadium came to be used as the name of the clause itself in modern (post-Latin) precedents, where it was translated literally. Burrill also draws a parallel to per quod, noting that words in a similar connection appear in old Latin writs of trespass under the Registrum Originale. This comparative observation is valuable for researchers tracing the structural vocabulary of Latin writs across different forms of action.
What the historical dictionaries do not address is the mechanics of gage itself—what the pledge consisted of, who served as surety, and how failure of the gage was handled. Researchers needing that procedural depth must go to Blackstone directly or to dedicated treatises on common law process. The dictionary entries treat per vadium as a gloss entry rather than a substantive doctrinal analysis.
Encyclopedia Cross-Reference
No Law Mind Encyclopedia entry directly addresses old writ procedure or gage-based attachment. The matching entries returned (Negligence Per Se, Physical Takings Per Se Rules, Defamation Per Se) share only the Latin prefix "per" and are not relevant to this term.