<P> In the 12th century, Henry II took a major step in developing the jury system . Henry set up a system to resolve land disputes using juries . A jury of twelve free men were assigned to arbitrate in these disputes . Unlike the modern jury, these men were charged with uncovering the facts of the case on their own rather than listening to arguments in court . Henry also introduced what is now known as the "grand jury", through his Grand Assize . Under the assize, a jury of free men was charged with reporting any crimes that they knew of in their hundred to a "justice in eyre," a judge who moved between hundreds on a circuit . A criminal accused by this jury was given a trial by ordeal . Under the jury, the chances of being found guilty were much lower, as the king did not choose verdict (or punishment). </P> <P> The Church banned participation of clergy in trial by ordeal in 1215 . Without the legitimacy of religion, trial by ordeal collapsed . The juries under the assizes began deciding guilt as well as providing accusations . The same year, trial by jury became a fairly explicit right in one of the most influential clauses of Magna Carta, signed by King John . Article 39 of Magna Carta reads (translated by Lysander Spooner in his Essay on the Trial by Jury (1852)): </P> <P> No free man shall be captured or imprisoned or disseised of his freehold or of his liberties, or of his free customs, or be outlawed or exiled or in any way destroyed, nor will we proceed against him by force or proceed against him by arms, but by the lawful judgment of his peers or by the law of the land . </P> <P> Although the charter says or by the law of the land, this in no manner can be interpreted as if it were enough to have a positive law, made by the king, to be able to proceed legally against a subject . The law of the land was the consuetudinary law, based on the customs and consent of King John's subjects and, since there was no Parliament in those times, neither the king nor the barons could make a law without the consent of the people . According to some sources, in the time of Edward III, by the law of the land had been substituted by due process of law, which in those times was a trial by twelve peers . </P>

Where did the idea of jury of our peers come from