Effective representation of the interests of the people
A modern advocate of sortition, political scientist John Burnheim, argues for sortition as follows:
But do we, in order to have democracy, have to find a way in which the demos first makes up its mind what is to be done and then controls its representatives in the process of carrying it out? What I want to suggest is a different conception. Let the convention for deciding what is our common will be that we will accept the decision of a group of people who are well informed about the question, well-motivated to find as good a solution as possible and representative of our range of interests simply because they are statistically representative of us as a group. If this group is then responsible for carrying out what it decides, the problem of control of the execution process largely vanishes. Those directing the execution process are carrying out their own decisions. They may need a little prodding to keep them up to the mark, but there is no institutional basis for a conflict of interest between bodies responsible for making decisions and those responsible for execution. They have an overriding interest in showing that their decisions are practical and well-grounded.
Fairness and equality
Sortition is inherently egalitarian in that it ensures all citizens have an equal chance of entering office irrespective of any bias in society:
Compared to a voting system – even one that is open to all citizens – a citizen-wide lottery scheme for public office lowers the threshold to office. This is because ordinary citizens do not have to compete against more powerful or influential adversaries in order to take office, and because the selection procedure does not favour those who have pre-existing advantages or connections – as invariably happens with election by preference. From an organisational point of view a citizen-wide lottery system gives all citizens an equal stake in the office in question and so defines the size of the active (or potentially active) citizen body.
Random selection overcomes the various demographic biases in race, religion, sex, etc. apparent in most legislative assemblies. Greater perceived fairness can be added by usingstratified sampling. For example the Citizens’ Assembly on Electoral Reform in British Columbia sampled one woman and one man from each electoral district and also ensured representation for First Nations members. Bias may still exist if particular groups are purposefully excluded from the lottery such as happened in Ancient Athens where women, slaves, younger men and foreigners were not eligible.
Greek writers who mention democracy (including Aristotle, Plato and Herodotus) emphasise the role of selection by lot or state outright that being allotted is more democratic than elections. For example Plato says:
Democracy arises after the poor are victorious over their adversaries, some of whom they kill and others of whom they exile, then they share out equally with the rest of the population political offices and burdens; and in this regime public offices are usually allocated by lot.
Less corruptible than elections
Sortition may be less corruptible than voting. Author James Wycliffe Headlam explains that the Athenian Council (500 administrators randomly selected), would commit occasional mistakes such as levying taxes that were too high. Additionally, from time to time, some in the Council would improperly make small quantities of money from their civic positions. However, “systematic oppression and organized fraud were impossible”. These Greeks recognized that sortition broke up factions, diluted power, and gave positions to such a large number of disparate people that they would all keep an eye on each other making collusion fairly rare. Furthermore, power did not necessarily go to those who wanted it and had schemed for it. The Athenians used an intricate machine, a kleroterion, to allot officers. Headlam also explains that “the Athenians felt no distrust of the lot, but regarded it as the most natural and the simplest way of appointment”.
Like Athenian democrats, critics of electoral politics in the 21st-century argue that the process of election by vote is subject to manipulation by money and other powerful forces and because legislative elections give power to a few powerful groups they are believed to be less democratic system than selection by lot from amongst the population.
Power to ordinary people
An inherent problem with electoral politics is the over-representative of the politically active groups in society who tend to be those who join political parties. For example in 2000 less than 2%  of the UK population belonged to a political party whilst in 2005 there were at best only 3 independent MPs (see List of UK minor party and independent MPs elected) so that 99.5% of all UK MPs belonged to a political party. As a result political members of the UK population were represented by one MP per 1800 of those belonging to a party whilst those who did not belong to a party had one MP per 19 million individuals who did not belong to a party.[verification needed]
Loyalty is to conscience not to political party
Elected representatives typically rely on political parties in order to gain and retain office. This means they often feel a primary loyalty to the party and will vote contrary to conscience to support a party position. Representatives appointed by sortition do not owe anything to anyone for their position.
Pure sortition does not discriminate
The most common argument against pure sortition (that is, with no prior selection of an eligible group) is that it does not discriminate those selected and takes no account of particular age, skills or experience that might be needed to effectively discharge the particular offices filled. Just as the Athenians did not choose generals (Strategos) by lot, today most would agree that random selection from the general population would not be a good way of filling the role of medical surgeon or aircraft pilot due to the specialist skills that those roles require. Only if the group had sufficient means to select an external specialist to do the actual work would it be able to overcome this.
For many political offices as, under a system based on election, it is thought unlikely that those manifestly lacking the requisite skills will be elected to office. According to Xenophon(Memorabilia Book I, 2.9), this classical argument was offered by Socrates:
[Socrates] taught his companions to despise the established laws by insisting on the folly of appointing public officials by lot, when none would choose a pilot or builder or flautist by lot, nor any other craftsman for work in which mistakes are far less disastrous than mistakes in statecraft.
The same argument is also made by Edmund Burke in his essay Reflections on the Revolution in France (1790):
There is no qualification for government but virtue and wisdom, actual or presumptive. […] Everything ought to be open, but not indifferently, to every man. No rotation; no appointment by lot; no mode of election operating in the spirit of sortition or rotation can be generally good in a government conversant in extensive objects. Because they have no tendency, direct or indirect, to select the man with a view to the duty or to accommodate the one to the other.
Because it introduces randomness in determining outcomes, there is always the statistical possibility that sortition may put into power an individual or group that do not represent the views of the population from which they were drawn. This argument is mentioned by Isocrates in his essay Areopagiticus (section 23): But, just as with any sample measurement the error rate can be reduced by increasing the sample.
[It was] considered that this way of appointing magistrates [i.e., elections] was also more democratic than the casting of lots, since under the plan of election by lot chance would decide the issue and the partizans of oligarchy would often get the offices; whereas under the plan of selecting the worthiest men, the people would have in their hands the power to choose those who were most attached to the existing constitution.
Voting confers legitimacy
Those who see voting as expressing the “consent of the governed“, maintain that voting is able to confer legitimacy in the selection. According to this view, elected officials can act with greater authority than when randomly selected. With no popular mandate to draw on, politicians lose a moral basis on which to base their authority. As such, politicians would be open to charges of illegitimacy, as they were selected purely by chance.
Enthusiasm of the representatives
Accountability In an elected system, the representatives are to a degree self-selecting for their enthusiasm for the job. Under a system of pure, universal sortition the individuals are not chosen for their enthusiasm. Many electoral systems assign to those chosen a role as representing their constituents; a complex job with a significant workload. Elected representative choose to accept any additional workload; voters can also choose those representatives most willing to accept the burden involved in being a representative. Individuals chosen at random from a comprehensive pool of citizens have no particular enthusiasm for their role and therefore may not make good advocates for a constituency.
Unlike elections, where members of the elected body may stand for re-election, sortition does not offer a mechanism by which the population expresses satisfaction or dissatisfaction with individual members of the allotted body. Thus, under sortition there is no formal feedback, or accountability, mechanism for the performance of officials, other than the law.