Selection by lot (allotment)

The use of a lottery to select officeholders was regarded as the most democratic means: elections would favour those who were rich, noble, eloquent and well-known, while allotment spread the work of administration throughout the whole citizen body, engaging them in the crucial democratic experience of, to use Aristotle's words, "ruling and being ruled in turn" (Politics 1317b28–30). The allotment of an individual was based on citizenship rather than merit or any form of personal popularity which could be bought. Allotment therefore was seen as a means to prevent the corrupt purchase of votes and it gave citizens a unique form of political equality as all had an equal chance of obtaining government office. Samons writes that "the system of selection by lottery for members of the Council of 500 and other officials (like the treasurers of the sacred funds) provided a potentially significant check on the dangers of demagoguery." However, this may not have been completely successful, as some "increasingly pandered to the electorate and ... often told the people only what they wanted to hear."
The random assignment of responsibility to individuals who may or may not be competent has obvious risks, but the system included features meant to obviate possible problems. Athenians selected for office served as teams (boards, panels). In a group someone will know the right way to do things and those that do not may learn from those that do. During the period of holding a particular office everyone on the team is observing everybody else. There were however officials such as the nine archons, who while seemingly a board carried out very different functions from each other.
No office appointed by lot could be held twice by the same individual. The only exception was the boule or council of 500. In this case, simply by demographic necessity, an individual could serve twice in a lifetime. This principle extended down to the secretaries and undersecretaries who served as assistants to magistrates such as the archons. To the Athenians it seems what had to be guarded against was not incompetence but any tendency to use office as a way of accumulating ongoing power.


Source : http://en.wikipedia.org/wiki/Athenian_democracy