Definition
Plegii de prosequendo (Latin: "pledges for prosecuting") is an archaic procedural term from common law pleading referring to sureties or pledges given by a plaintiff as a guarantee that the plaintiff would prosecute the action through to judgment. In early common law practice, before a plaintiff could proceed with certain actions, particularly real actions and actions on the case, the court required the plaintiff to name pledges — typically fictitious persons — who stood as nominal guarantors that the suit would be diligently pursued and not abandoned. The pledges bore no actual liability; the practice was almost entirely formal and ceremonial in nature.
The phrase appears most commonly in the formal record of writs and declarations at the foot of the plaintiff's pleading, where the pledges (frequently named "John Doe and Richard Roe" or their equivalents) were entered of record. Their sole function was to assure the court that prosecution of the suit would continue.
Why It Matters in Research
Researchers working in early English and American common law records — particularly those predating the procedural reforms of the nineteenth century — will encounter plegii de prosequendo as a routine entry at the foot of declarations and writs. Its presence in a document is a reliable marker that the record belongs to the pre-reform era of common law pleading, before the Field Code reforms in the United States (beginning 1848) and the English Judicature Acts (1873–1875) swept away formal common law pleading requirements.
Because the pledges were invariably fictitious, these entries carry no substantive legal significance and should not be read as identifying real parties or real sureties. Researchers tracing parties to a lawsuit should not be misled by the names appearing as pledges.
The term is closely associated with the parallel fiction of pledges in replevin — plegii de retorno habendo — and with the broader world of fictitious procedural devices that characterized classical common law practice. Understanding that plegii de prosequendo is a formality, not a substantive surety arrangement, is essential for correctly reading and transcribing early court records.
The term will not appear in post-reform pleading records. Its absence from a document of the same era can occasionally signal that a record is incomplete or that a particular court had already relaxed the formal requirement.
Historical Dictionary Support
Rapalje and Lawrence treat plegii de prosequendo briefly but accurately, defining it as "pledges to prosecute," and situating it within their discussion of common law pleading formalities. They note its essentially fictitious character without elaboration, which reflects the term's status by 1883 as an antiquarian survival rather than a live procedural requirement. Their entry captures the consensus view across historical legal dictionaries: the pledge was nominal, the names were conventional, and the institution had no practical teeth.
Earlier English authorities, including Blackstone in his Commentaries and Chitty in his treatise on pleading, describe the pledges as a pure formality that had long since lost any original coercive function, if it ever had one. Jacob's Law Dictionary and Tomlin's Law Dictionary similarly treat the institution as a formal remnant. None of the historical sources identify a meaningful enforcement mechanism for the pledge, reinforcing that by the eighteenth century the practice was wholly ceremonial.
What historical dictionaries do not address is the documentary significance of these entries for later archival researchers — that is, how to use the presence or absence of plegii de prosequendo as a dating and authenticity signal in manuscript court records. That interpretive function has to be supplied by the researcher from context.
Jurisdictional Note
The practice was inherited by American courts from English common law and was observed in jurisdictions that followed formal common law pleading prior to code reform. It was eliminated in American jurisdictions that adopted the Field Code or equivalent procedural reforms, and has no presence in modern civil procedure under the Federal Rules or their state equivalents.