Definition
"By the judgment of their peers in [our] court." A Latin phrase drawn from the original text of Magna Carta (1215), specifically from the provision — later codified as Chapter 29 of the 1225 reissue — forbidding the Crown from proceeding against a free person except by the lawful judgment of that person's peers or by the law of the land. The phrase appears in the grant made by King John to his barons and encapsulates one of the earliest formal constraints on arbitrary royal power: that judgment must come from equals assembled in a court of law, not from the sovereign's unilateral command.
The full operative context reads, in substance: the Crown will not seize, disseise, imprison, outlaw, exile, or otherwise proceed against a free person unless by the judgment of their peers in court (per judicium parium suorum in curia) or by the law of the land (per legem terrae). The two clauses — judicium parium and lex terrae — were historically understood as alternative procedural guarantees, not synonyms, though later commentary often treated them as a unified due process principle.
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Common Confusion
The phrase is frequently collapsed into the modern concept of "trial by jury," but the equation is imprecise. The peers referenced in Magna Carta were social and feudal equals — barons judging barons — not a randomly drawn panel of twelve citizens. The jury as a constitutional institution evolved from a distinct procedural tradition and was not fully identified with the judicium parium guarantee until later common law development conflated the two. Researchers encountering either phrase in medieval or early modern sources should not assume the modern jury trial is what the text contemplates.
The phrase is also sometimes confused with the separate Magna Carta guarantee of per legem terrae ("by the law of the land"), which fed into the American due process clauses. The two guarantees share ancestry but carry different doctrinal histories.
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Why It Matters in Research
This phrase is a primary source anchor, not a working legal doctrine. Researchers will encounter it in several distinct contexts that require different handling:
**Magna Carta scholarship and constitutional history.** The phrase appears in treatises, commentaries, and judicial opinions tracing the lineage of due process guarantees. Blackstone's edition of Magna Carta (cited in Burrill) and Coke's Second Institutes were the dominant transmission channels through which this phrase entered Anglo-American constitutional argument. Any research into the historical foundations of due process, jury trial rights, or habeas corpus will eventually pass through this language.
**Feudal and medieval law sources.** In its original context the phrase operated within a feudal court structure. "Peers" meant tenants of the same lord, equals in tenure and status. The "curia" was the lord's court. Projecting modern courtroom assumptions backward distorts the original meaning. Sources predating the seventeenth century use the phrase in this feudal register; sources from Coke onward tend to read it anachronistically through common law categories.
**Transformation over time.** The critical interpretive move — treating judicium parium as the ancestor of trial by jury — was largely the work of seventeenth-century common lawyers, especially Coke, who used Magna Carta as political ammunition against Stuart prerogative. That interpretive tradition became canonical in England and America, but it was a construction, not an obvious reading of the 1215 text. Researchers working on originalist arguments, or on the intellectual history of due process, need to track the construction rather than treat it as settled history.
**American constitutional usage.** The phrase migrated into American constitutional discourse through Blackstone and Coke. It surfaces in founding-era debates over jury rights and in early American due process cases. When nineteenth-century American courts invoke Magna Carta in due process analysis, they are almost always invoking the Coke-Blackstone reading of this phrase, not the feudal original.
**Trap for the unwary.** The Patent Roll citation (Pat. 16 Johan. pars 1, m. 3, d. n. 2) referenced in Burrill points to the original grant enrolled in Chancery. Researchers consulting that document directly should be aware they are reading a political concession extracted under duress in 1215, subsequently annulled by Pope Innocent III, and only restored and reissued in modified forms under Henry III. The 1215 text and the 1225 reissue differ; most constitutional citation runs to the 1225 version or its statutory confirmations.
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Historical Dictionary Support
Burrill's entry preserves the Latin text of the grant with an English translation and cites both the original Patent Roll enrollment and Blackstone's edition of Magna Carta. Burrill's treatment is characteristically documentary — he records the text and its source references rather than synthesizing the doctrinal development — which makes the entry useful as a primary text locator but thin as constitutional analysis.
The entry does not address the distinction between the 1215 and 1225 texts, does not engage with Coke's interpretive transformation of the phrase, and does not trace the American reception. Researchers relying solely on Burrill will have the phrase correctly identified but will miss the contested interpretive history that gives the phrase its significance.
What Burrill captures well is the feudal and royal context: the language of royal grant ("we have granted to our barons who are against us"), the coercive circumstances of 1215, and the enrollment in Chancery records. These details matter for researchers working in medieval legal history or primary source paleography.
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Jurisdictional Note
The phrase has no operative force as independent legal doctrine in modern Anglo-American courts. Its significance is constitutional-historical. In the United States, the guarantee it represents has been absorbed into the Due Process Clauses of the Fifth and Fourteenth Amendments. In England, Magna Carta has been largely superseded by statute, though it retains symbolic and occasional interpretive significance.
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Encyclopedia Cross-Reference
See Law Mind Encyclopedia: Magna Carta — for the full text, reissues, and constitutional reception.
See Law Mind Encyclopedia: Due Process of Law — for the American doctrinal development from this phrase through modern constitutional guarantees.
See Law Mind Encyclopedia: Trial by Jury — for the relationship between judicium parium and the common law jury.
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