# Hare–Clark electoral system

A Hare-Clark ballot paper for the electorate of Brindabella in the 2016 Australian Capital Territory general election.

Hare-Clark is a type of single transferable vote electoral system of proportional representation used for elections in Tasmania and the Australian Capital Territory. The method for the distribution of preferences is similar to other voting systems in Australia, such as for the Australian Senate.

The name is derived from English barrister, Thomas Hare, and the Attorney-General of Tasmania, Andrew Inglis Clark, who first introduced the modified counting system to Tasmania in 1896.

## History

Thomas Hare (1806–91) is generally credited with the conception of the single transferable vote, while Andrew Inglis Clark (1848–1907) introduced the system to Tasmania with a modified counting method. "The specific modification introduced by Mr A I Clark, Attorney-General for Tasmania, is the provision devised by him for eliminating the element of chance in the selection and distribution of quota-excesses or surplus transfer votes."[1] The provision described as "Clark's own" was to transfer all votes to 'next order of preference', rather than a random sample.[2]

In 1896, after several failed attempts, Clark was able to get a system of proportional representation adopted by the Tasmanian Parliament, but it was to be only on a trial basis for both Hobart (to elect 6 MPs) and Launceston (to elect 4 MPs). This first 'Hare-Clark system', as it was immediately known, was renewed annually until suspended in 1902. Clark, never in robust health, died at his home 'Rosebank' in Battery Point on 14 November 1907, just as permanent proportional representation struggled through Parliament and over a year before it was used for the first time throughout Tasmania at the general election in April 1909.[2]

Hare-Clark has been used continuously for Tasmanian state elections since 1909[3] for the House of Assembly. The Legislative Council[4] is elected by the same system as is used to elect members of the Australian House of Representatives.[4] The Hare-Clark System was adopted to be used for the Australian Capital Territory Legislative Assembly in 1992.[5][6]

### Evolution

Features of Hare-Clark have evolved over time. Until 1942, candidates were listed in alphabetic order rather than grouped together by party.[3] Robson Rotation, where the order candidates appeared on ballot papers is randomised, was introduced in 1980. This has the effect of reducing any advantage a candidate has by appearing at the top of a party list,[7] so as to eliminate any influence of the so-called "donkey vote".

## Counting

After a candidate reaches a quota and is elected, all of their ballot papers are distributed to elect further candidates (according to the voters next preference on each ballot paper). The distributed votes have a lesser transfer value which depends on the excess number of votes the previously elected candidate received. If no candidates are elected, the candidate with the fewest votes is eliminated and their preferences are distributed accordingly.

In terms of how the count is conducted, there are only minor differences between Hare-Clark and Australian Senate style systems prior to the abolishment of group voting tickets prior to the 2016 Australian federal election.[8] The Senate system allowed 'above the line' voting where the party would determine the order that preferences would be distributed to other candidates. The option for a voter to have their preferences determined by group voting tickets is still used in Victoria and Western Australia. In contrast, under Hare-Clark preferences are always determined explicitly by individual voters. The distribution of how-to-vote cards outside polling places on election day is also banned.[3]

### Counting method with example

1. Initial count

Any invalid votes are excluded (e.g. no boxes marked) and then the first preferences from each ballot paper is tallied
 Example: Of the total 10,500 votes cast by the electorate, 500 are invalid.There are 10,000 valid votes remaining.

2. Determining the quota

The total count of valid votes is used to calculate the quota of votes required for a candidate to be declared elected.
${\displaystyle {\mbox{quota to be elected}}=\left({{\rm {\mbox{total valid votes +1}}} \over {\rm {\mbox{number of vacancies}}}+1}\right)}$
 Example: There are 10,000 valid votes and 3 vacancies to be filled. quota to be elected(x)=((10000+1)/(3+1)) x = 2500.25 The quota to be elected is 2501 votes.

3. Declaring candidates elected

Candidates are elected when they have the required quota of votes; any surplus votes are distributed as outlined in 4 below. If no candidates have a surplus of votes and there are vacancies remaining the count proceeds to 5. The count is complete if there are no remaining vacancies.
 Example: Candidate PLATYPUS receives 3,000 first preference votes, and is more than the quota of 2,501.Candidate PLATYPUS is declared elected.

The number of votes in excess of the quota is a surplus of votes. The number of surplus votes is used to determine the transfer value of distributed preferences from the candidate.
4a. The transfer value is determined
${\displaystyle {\mbox{transfer value}}=\left({{\rm {\mbox{surplus votes}}} \over {\rm {\mbox{last votes received}}}}\right)}$
 Example: Candidate PLATYPUS has 3,000 first preference votes, which is a 499 surplus above the quota. Transfer value(x)=(499/3000) (x)=0.17 The transfer value from PLATYPUS is 0.17.
4b. Distribution of preferences
The preferences from the elected candidate is tallied using all of their ballot papers, and is distributed at the rate of the transfer value.
${\displaystyle {\mbox{value of distributed preferences}}={\mbox{transfer value}}*{\mbox{number of preferences}}}$
 Example: Of the 3,000 first preference votes for Candidate PLATYPUS, 1,000 had Candidate WOMBAT as second preference. WOMBAT receives these votes but at the value of the transfer rate. ${\displaystyle {\mbox{170}}=0.17*1,000}$ Candidate WOMBAT has 170 added to their total.
4c. Counting the new totals

5. Remaining candidates have not reached the quota

When there are still vacancies, but all the remaining candidates are equal to or less than the quota, the candidate with the lowest current vote is excluded. The preferences of the excluded candidate is then distributed and new candidate totals are counted (return to 3). The count is complete if the number of candidates remaining is the same as remaining vacancies.
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