Definition
"Et petit auxilium" is a Latin pleading formula meaning "and he prays aid." It was the operative phrase by which a defendant in a common law action invoked the procedural device known as a prayer for aid (or aid prayer), requesting that the court pause the principal proceeding and summon a third party — typically one with a superior or concurrent interest in the subject matter — to assist in the defense. The phrase appeared as a set form in the written pleadings of the medieval and early modern English courts and signaled the formal commencement of the aid prayer process.
Common Confusion
"Et petit auxilium" is sometimes loosely conflated with related Latin formulae appearing in the same plea roll contexts, including "et petit auxilium de rege" (a prayer for aid from the Crown, available to tenants holding directly of the king) and the distinct concept of vouching to warranty. These are related but separate devices: vouching to warranty compelled a warrantor to defend title, while a prayer for aid brought in a co-interested party without the same compulsory character. The structural similarity of the formulas in plea rolls can mislead researchers into treating them as interchangeable.
Why It Matters in Research
This phrase is almost exclusively a research artifact of Year Book pleading records and early common law practice materials. It will not appear in modern procedural codes or contemporary case law. Researchers encountering "et petit auxilium" in a primary source are working with common law pleading from the medieval or early modern period — most likely an English Year Book, a plea roll, an early abridgment, or a treatise in the Littleton–Coke tradition.
The phrase functions as a navigational marker: its presence in a document signals that the pleading concerns a possessory or proprietary action (typically real property) in which the defendant lacked a complete defense standing alone and needed the procedural protection of delay and third-party assistance. Real actions — writs of right, writs of entry, novel disseisin, and their variants — are the most common contexts.
One research trap: the abbreviated Latin of plea rolls frequently drops surrounding context, and "et petit auxilium" may appear without clear identification of who is praying aid, from whom, and on what basis. Cross-referencing Burrill's citation to the Year Books of Edward II's reign is useful for understanding the baseline procedural expectations of the device at the time the formula was crystallized in written practice.
For corpus researchers working in Law Mind materials, this term connects the Year Book tradition to the systematic pleading treatises of the seventeenth and eighteenth centuries, where the prayer for aid received more analytical treatment. Researchers should follow the cross-reference to "Similiter" and related plea forms to reconstruct the full procedural sequence in which "et petit auxilium" operated.
Historical Dictionary Support
Burrill's Law Dictionary provides the essential gloss: "And he prays aid," with a citation to the Year Books of Michaelmas term, 1 Edward II. This is a tight, accurate entry of the kind typical of Burrill — it identifies the phrase, translates it, and anchors it to a primary source without elaboration. Burrill does not analyze the underlying procedure or distinguish the variants of the aid prayer, leaving that work to the researcher.
Burrill's placement of "et petit auxilium" immediately adjacent to "et prædictus A. similiter" (the Latin formula for the similiter in pleading) reflects the organizational logic of the historical dictionaries: these entries were catalogued as Latin pleading forms, not as substantive doctrinal concepts. This is accurate to their function — they are formulaic phrases of art whose meaning lies in their procedural context, not in the words themselves.
No other standard historical law dictionaries in common circulation provide meaningfully deeper treatment of this specific phrase. Researchers requiring substantive analysis of the aid prayer procedure itself should consult Blackstone's Commentaries (Book III), Fitzherbert's Natura Brevium, or the relevant Year Book abridgments, none of which are adequately substituted by dictionary entries alone.
Jurisdictional Note
"Et petit auxilium" as an operative pleading formula is specific to the English common law courts and their direct inheritors. American courts adopted common law pleading forms in the colonial and early federal periods, but the prayer for aid as a distinct procedural device had largely fallen into disuse or been superseded by equity procedure and, later, code pleading reforms well before American practice consolidated. The phrase has no meaningful modern procedural analog in any U.S. jurisdiction.