Definition
A writ of medieval English law by which a person threatened with death or bodily harm by another could compel that threatening party to give security for the peace. The writ ran against the person making the threats, requiring them to provide surety that they would keep the peace toward the complainant. The action was preventive rather than remedial — its purpose was to forestall violence before it occurred, not to punish harm already done.
Securitatis pacis is the Latin name for what was commonly called a writ for surety of the peace, and it is the historical ancestor of the modern peace bond and related protective proceedings.
Common Confusion
Securitatis pacis is often conflated with the general concept of "surety of the peace," which in later practice became available through a justice of the peace by summary proceeding rather than by original writ. The distinction matters for historical research: the writ form described under this Latin name belongs to early common law pleading practice and largely gave way to the magistrate-based procedure well before the early modern period. A researcher encountering "surety of the peace" in post-seventeenth-century sources is almost certainly dealing with the summary process, not this writ.
Why It Matters in Research
This term appears almost exclusively in sources dealing with early English common law writs and pleading, and it is essentially obsolete as a live procedural form. Researchers will encounter it in three contexts: (1) historical surveys of the Register of Original Writs, where it appears as a catalogued writ form; (2) treatises on the peace bond and its ancestry, where securitatis pacis marks the origin point of a long procedural lineage; and (3) Latin legal texts or abridgments where the English gloss "surety of the peace" has been replaced by or used alongside the Latin form.
The critical research trap is anachronism. The writ form described here had been superseded in practical use long before most American legal sources were written. When American courts or treatise writers reference the surety of the peace, they are drawing on the magistrate-based descendant of this writ, not the original writ itself. Attempting to reconstruct the elements or scope of modern peace bond proceedings from sources defining securitatis pacis will produce a distorted picture.
Note also that the historical dictionaries cite the Registrum Omnium Brevium (Reg. Orig.) as authority. Researchers tracing the writ to that source should be aware that different editions of the Register carry different pagination, which accounts for the minor discrepancy between Bouvier (citing page 98) and Black's and Rapalje (citing page 88). Both references are to the same source document; neither citation is erroneous on its face.
Historical Dictionary Support
Black's Law Dictionary, Rapalje & Lawrence, and Bouvier's Law Dictionary are in close agreement on this term — all three define it as a writ available to one threatened with death or bodily harm against the person making such threats, and all three anchor the definition to the Registrum Omnium Brevium. The entries are brief and largely derivative of one another, which is typical for obsolete writ forms where the historical dictionaries are recording rather than analyzing.
What the historical dictionaries do not supply: any account of how the writ was actually initiated, what form of security was required, what procedure governed it, or how it related to the justice of the peace's concurrent and ultimately dominant authority. Researchers needing that functional account must go to treatises on early English criminal procedure and the development of the peace bond — the dictionary entries alone do not support substantive reconstruction of the writ's operation.
Jurisdictional Note
Securitatis pacis as a formal writ never took root in American jurisdictions, which received the summary magistrate process for surety of the peace rather than the original writ form. The term is therefore a matter of English legal history for American researchers, though the proceeding it represents — compelling a threatening party to give security for future peaceable conduct — has direct American descendants in the form of peace bonds and, more recently, civil harassment restraining orders.