Definition
Per pares (Latin: "by peers") is a phrase from medieval English law denoting the right of a free person — particularly a feudal tenant or nobleman — to be tried or judged by his peers, that is, by persons of equal rank and status. The concept is most closely associated with Magna Carta's guarantee that no free man shall be seized, imprisoned, or dispossessed except by the lawful judgment of his equals (per pares suos) and by the law of the land.
The phrase captures two connected ideas: first, that judgment belongs to the community of equals rather than to a superior acting alone; second, that the composition of the judging body matters — a lord could not be condemned by inferiors, and a serf could not claim the same tribunal as a knight. Status determined who qualified as a "peer" in the adjudicatory sense.
Why It Matters in Research
Per pares is primarily a term of historical and constitutional significance rather than a living doctrine. Researchers encounter it most often in three contexts:
1. Magna Carta scholarship. The phrase anchors the famous Chapter 29 (renumbered from Chapter 39 in the 1215 original) guarantee of judgment per legem terrae — "by the law of the land." Understanding per pares is essential to tracing how that clause evolved into modern due process and jury-trial guarantees. The medieval meaning, however, was status-specific and hierarchical; its transformation into a universal right of jury trial was a long, contested development, not an obvious implication of the original text.
2. Feudal tenure and manorial court research. In the context of feudal land law, per pares described the requirement that disputes over tenure be resolved in the lord's court by fellow tenants of equivalent standing. Researchers working with medieval court rolls, Year Books, or early common law treatises (Glanvill, Bracton) will encounter the concept embedded in discussions of novel disseisin and feudal forfeiture. Do not assume the modern jury-trial right maps cleanly onto these early usages.
3. Constitutional history. American and English constitutional historians trace the lineage of jury trial, due process, and the right to be heard by one's peers directly through per pares. The phrase appears in Coke's commentaries on Magna Carta, which were enormously influential in framing English and American constitutional argument. Coke's reading of per pares suos as guaranteeing trial by jury was itself a sixteenth- and seventeenth-century reinterpretation, not the straightforward medieval meaning.
The trap for researchers: do not retroject modern egalitarian notions of "peers" back into the medieval sources. Per pares was explicitly a status-bound concept. The modern jury of one's "peers" has shed the hierarchical requirement entirely.
Historical Dictionary Support
Burrill's Law Dictionary provides a minimal but accurate entry: "By the peers. Per pares suos; by their peers. Mag. Cart. 9 Hen. III. c. 14." The citation is to the 1225 reissue of Magna Carta under Henry III, which became the version enrolled on the statute rolls and treated as authoritative in subsequent English law.
Burrill's brevity reflects the term's status as a fixed Latin formula rather than a contested doctrinal concept by the nineteenth century. The phrase had been largely absorbed into broader discussions of Magna Carta, jury trial, and constitutional liberty; it needed no extended definition because its context was assumed.
What Burrill does not supply — and what researchers should seek elsewhere — is the developmental arc: how per pares shifted from a feudal-hierarchical concept to a constitutional touchstone. For that analysis, Coke's Second Institutes and Blackstone's Commentaries (Book III, on jury trial) are the key secondary sources. Neither is reproduced in Burrill's entry, making this a case where the historical dictionary is a signpost, not a destination.
Jurisdictional Note
Per pares is a term of English medieval and constitutional law. Its direct doctrinal relevance in American law is historical rather than operative — American courts do not apply the phrase as a live standard, but constitutional provisions protecting jury trial and due process are understood against its backdrop. Scottish and continental feudal systems had analogous but distinct concepts; do not assume the English per pares maps onto French or German feudal law without verification.