Blackballing

Blackballing is a rejection in a traditional form of secret ballot, where a white ball or ballot constitutes a vote in support and a black ball signifies opposition. This system is typically used where a club's rules provide that one or two objections, rather than an at-least-50% share of votes, are sufficient to defeat a proposition. Since the seventeenth century, these rules have commonly applied to elections to membership of many gentlemen's clubs and similar institutions such as Freemasonry and fraternities.

A large supply of black and white balls is provided for voters. Each voter audibly casts a single ball into the ballot box under cover of the box, or of a combination of a cloth and the box itself, so that observers can see who votes but not how they are voting. When all voting is complete, the box is opened and the balls displayed: all present can immediately see the result, without any means of knowing which members are objecting.

The principle of such election rules in a club is that it is self-perpetuating to preserve the current ethos (and exclusivity) of the club, by ensuring that candidates are congenial to (almost) all the existing members; i.e., new members are elected by unanimous or near-unanimous agreement of voting members. A difference of opinions could be divisive, so that an election must be taken secretly as well as correctly.

The number of votes in support is often irrelevant, except to prove a quorum. Whilst in many such cases even a single black ball will be fatal to the candidate's election, rules in larger clubs ensure that a single member cannot exercise a veto to the detriment of the future of the club. For example, two black balls are required to exclude; a limited category or committee of members vote, rather than all members; or in the event of a blackball, the election may be repeated immediately to ensure that there is no mistake, or after a fixed period to allow further information or opinions to be discussed discreetly. A variant sometimes used is that all incoming candidates are voted on as a group; if the group as a whole is blackballed, then each member must be voted on individually.

The practice also found popularity in areas outside of social clubs. In the Soviet Union, dissertation panels would typically cast their vote on a thesis defense using this system.

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