The Assize of Clarendon, 1166

Once Henry II had established his authority over England, he turned his attention to the legal system of his new country.  He understood, as did most kings of the Medieval era, that royal authority was only as strong as the law.  If wrongdoers were being punished and disputes settled, people would have more respect and fear for royal authority.  Henry had inherited a kingdom were Saxon and Norman customs prevailed.  There was some idea of a jury and of local courts, but these were heavily influenced by customs routed in superstition and susceptible to being swayed by those with more money or popularity.

Trial by combat, where parties to a case or more likely, hired champions, would fight to determine the outcome was still the norm in most civil or criminal cases.  In criminal cases as well there was trial by ordeal, where an accused would be forced to walk over hot coals, hold a red hot bar in their hand, or plunge their hand into boiling water and have their guilt determined by whether the injury became infected.  Wealthy or popular defendants could recruit their friends to swear to their innocence en masse, by a process known as compurgation.  In civil cases, the other side could round up their relatives and friends, forcing judges and juries to go with the more popular side in a given controversy.  Naturally, disgruntled victims and plaintiffs often resorted to taking justice into their own hands.  Henry wanted to put a stop to all this.

He began by setting up assizes or courts to handle property and other civil matters.  He also dispatched justices to travel the country and hold justice eyres.  Upon arriving in a town, the justices would command the local sheriff to convene twelve men whose responsibility it was to investigate any potential crimes in the area, the forerunner of a modern grand jury.  Once the suspects were caught, the jurors would question witnesses and make a determination of guilt, after which sentence would be pronounced and the guilty punished.  An acquittal still resulted in banishment, from either the town or village or even the kingdom for serious offenses, to avoid any private retributions or blood feuds.  As this system continued, there was need to formulate more efficient rules and procedures, which Henry proceeded to do.  During an assize held at Clarendon Castle in 1166, Henry and his advisors laid out the procedures by which judges and juries, not competing, swearing village factions, would determine the guilt or innocence and the right penalty to be applied in the case of the former. 

Under Henry's system, no one was above or immune to the law.  Clergymen and barons could be brought to trial and punished, or made to return property they had taken.  Henry's sense of justice drew no distinction between clergy and laity, a fact that would run him head-on into conflict with his Archbishop of Canterbury, Thomas Becket.  The barons were also irked and the conflict between royal and baronial authority would come to a head during John's reign in 1215.  However, on the whole, Henry's system for dispensing swift, regular and equal justice worked and would form the basis of what became the English common law system.