A few ideas to balance the US centric style.

Whilst you have brought in large area of British (mainly English and Welsh) facts neverthe less the opening paragraphs are somewhat US based.  I have no knowledge whatsoever on anything other than the UK perspective (though as this contributes significantly to US law, it will at least set some history.  

I am also a little bit concerned at why juries were created in the first place, you state that this is because they are believed to be free from bribery. Historically, trial by jury arose because of the difficulties of securing trial by ordeal, due to a change in church law.  By that time juries already sat to decide if there was a primae facie case to answer (the modern equivalent being Grand Juries).

The history of trial by jury (in England and hence the US) is related to several important events, most notebly the Assizes of Clarendon, the Fourth Lantern Council and the Magna Carta.

It may be useful for you to have a look at some of the wikipedia sites listed below:

http://en.wikipedia.org/wiki/Trial_by_ordeal

"In the Assize of Clarendon, enacted in 1166 and the first great legislative act in the reign of the English Angevin King Henry II, the law of the land required that: "anyone, who shall be found, on the oath of the aforesaid [a jury], to be accused or notoriously suspect of having been a robber or murderer or thief, or a receiver of them ... be taken and put to the ordeal of water."

http://en.wikipedia.org/wiki/Fourth_Lateran_Council

Canons 14-18. Rules on the conduct of the clergy including against such things as: non-celibate living, drunkenness, frequenting taverns, hunting, conducting trials by ordeal or combat 
http://en.wikipedia.org/wiki/Magna_Carta

Though you may be best considering the uk statute site which says:
http://www.statutelaw.gov.uk/content.aspx?activeTextDocId=1517519

"NO Freeman shall be taken or imprisoned, or be disseised of his Freehold, or Liberties, or free Customs, or be outlawed, or exiled, or any other wise destroyed; nor will We not pass upon him, nor [X5 condemn him,] but by lawful judgment of his Peers, or by the Law of the Land."

Kind Regards

Andy Cheetham

If you want to establish reasons for the use of a jury then it may be worth considering