Sheriffs

Originally sheriffs were elected by the people at a folkmoot. In Anglo-Saxon times the shire-reeve was considered to be equal of a bishop. By 1130, however, sheriffs were considered to be members of a new nobility, and were unlikely to be great barons. Indeed the post of sheriff in a given shire might, in actuality, be in the pocket of the local magnate.

A sheriff's legal duties at that time are described in the Assize of Clarendon (1166)

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

http://www.earlyenglishlaws.ac.uk/laws/texts/ass-clar/
The History of England. The Assize of Clarendon, 1166 - Documents in English History.

http://historyofengland.typepad.com/documents_in_english_hist/2012/10/the-assize-of-clarendon-1166.html.

Fiscal duties of a sheriff

Under Henry I, the procedure adopted for the audit of the sheriffs was formalised. This involved the Treasurer drawing up a summons in the form of a writ which was sent to each sheriff, which he was required to answer in person. The Treasurer then called on each sheriff to give a full account of the income in his shire due from the royal demesne lands and from the county farm. The Chancellor then questioned him concerning any debts owed by private persons to the king. The results of the audit were recorded in the Pipe Rolls.

These duties are described in the Dialogus.
http://avalon.law.yale.edu/medieval/excheq.asp#b2p3 

Inquest of Sheriffs 1170

In 1170 Henry II ordered an inquest to be held of all the activities undertaken by the sheriffs. After the inquest many were sacked and were replaced with more trustworthy persons. The new sheriffs owed their posts to the king.

http://www.fordham.edu/halsall/source/isheriffs.asp

http://ehr.oxfordjournals.org/content/XXXIX/CLIII/80.full.pdf+html

References

William Alfred Morris (1968). The Medieval English Sheriff to 1300. Manchester University Press. ISBN 978-0-7190-0342-4.

http://www.highsheriffs.com/History.htm

John Impey (20 October 2010). The Office of Sheriff, Shewing Its History and Antiquity: the Manner of Appointing the High Sheriff, His Under Sheriff, and Other Deputies; Together with Their Respective Powers and Duties. BiblioBazaar. ISBN 978-1-170-81295-2.

http://archive.org/details/practiceofoffice00impe

John Hudson (22 March 2012). The Oxford History of the Laws of England Volume II: 871-1216. Oxford University Press. pp. 507–. ISBN 978-0-19-163003-3.

George Garnett (28 April 1994). "Julia Boorman: The Sheriffs of Henry II and the Significance of 1170". Law and Government in Medieval England and Normandy: Essays in Honour of Sir James Holt. Cambridge University Press. pp. 255–.ISBN 978-0-521-43076-0.

http://conclarendon.blogspot.com/2013/06/currency-in-england-at-time-of-henry-ii.html

Hélène Débax (2008). Vicomtes et vicomtés dans l'Occident médiéval. Presses Univ. du Mirail. pp. 291–. ISBN 978-2-85816-942-9

Judith A. Green; Great Britain. Public Record Office (September 1990). English sheriffs to 1154. H.M.S.O.