(2): Per judicium parium:

every judgment must be delivered by the accused man’s “equals.” The need for “a judgment of peers” was recognized at an early date in England. It was not originally a class privilege of the aristocracy, but a right shared by all grades of free–holders; whatever their rank, they could not be tried by their inferiors. In this respect English custom did not differ from the procedure prescribed by feudal usage on the Continent of Europe. Two applications of this general principle had, however, special interest for the framers of Magna Carta: the “peers” of a Crown tenant were his fellow Crown tenants, who would normally deliver judgment in the Curia Regis; while the “peers” of the tenant of a mesne lord were the other suitors of the Court Baron of the manor. In either case, judgments were given per pares curiae. John, resorting wholesale to practices used sparingly in earlier reigns, had set these rules at defiance. His political and personal enemies were exiled, or deprived of their estates, by the judgment of a tribunal composed entirely of Crown nominees. Magna Carta promised a return to the ancient practice.

The varied meanings conveyed by the word “peers” to a medieval mind, together with the nature of judicium parium, may be further illustrated by the special rules applicable to four exceptional classes of individuals:—(a) Jews of England and Normandy enjoyed under John’s Charter of 10th April, 1201, the right to be judged by men of their own race; for them a judicium parium was a judgment of Jews. (b) A foreign merchant, by later statutes, obtained the right to a jury of the “half tongue” (de medietate linguae), composed partly of aliens of his own country. (c) The peers of a Welshman seem, in some disputes with the Crown, to have been men drawn from the marches: such at least is the plausible interpretation of the phrase “in marchia per judicium parium suorum,” occurring in later chapters of Magna Carta, and granting to the Welsh redress of wrongful disseisins. (d) A Lord Marcher occupied a peculiar position, enjoying rights denied to barons whose estates lay in more settled parts of England. In 1281 the Earl of Gloucester, accused by Edward I. of a breach of allegiance, claimed to be judged, not by the whole body of Crown tenants, but by such as were, like himself, lords marchers. These illustrations show that a “trial by peers” had a wider and less stereotyped meaning in the Middle Ages than it has at the present day.