The Hare-Clark counting system is used in Tasmania to elect five Members to each division of the Tasmanian House of Assembly.
Hare-Clark is a Single Transferable Vote (STV) method of proportional representation. STV means that a ballot paper moves between candidates as determined by the elector’s marked preferences. The Australian Senate also uses a proportional representation counting system, although their counting system has some significant differences to Hare-Clark.
Hare-Clark enables parties, groups and independents to be elected to the House of Assembly in proportion to their support in the division. In other words, compared to other counting systems, the composition of the House more closely reflects the proportion of primary votes for each party on a state-wide basis.
While the term Hare-Clark was originally given to just the process of counting votes, more recently it has taken on a broader meaning to also include a specific ballot paper configuration and rotation of candidate names (Robson Rotation).
Thomas Hare was an Englishman who, in 1856, proposed the idea of a proportional representation election system which was further developed and became known as the Hare system. Andrew Inglis Clark, Tasmania’s Attorney-General from 1887-92 and 1894-97, proposed a modified version of the Hare system which became Tasmanian law in 1896. This is now known as the Hare-Clark electoral system and it has been used statewide since 1907.
The ballot paper displays multiple columns of candidate names. Each registered political party can nominate candidates to appear in a single column under the party name. A group of other candidates can nominate to run together in a column however without a column title.
The order of these columns across the ballot paper is determined by a draw. All ungrouped candidates are listed in the final column.
Under Hare-Clark, electors must mark preferences for individual candidates unlike the Australian Senate ballot papers which include above-the-line voting where electors can choose a specific party or other column of candidates.
Robson rotation is a process of rotating candidate names within each column so that the advantage of appearing at the top of the column or directly below another popular candidate are shared equally between candidates. Neil Robson, a former member of the House of Assembly, introduced the process to the Tasmanian Parliament in 1979.
To be counted as a vote a ballot paper must have at least the numbers 1, 2, 3, 4, and 5 with no repetitions or omissions. Ballot papers with ticks or crosses, instead of numbers, cannot be counted.
A candidate is elected when his/her total number of votes equals or exceeds the quota. The quota is the lowest number of votes a candidate needs to be certain of being elected.
For House of Assembly elections, which elect five members to each division, the quota is calculated as one vote more than a sixth of the total formal votes. For example, if total formal votes were 600, the quota would be 101 (1/6 of total + 1 vote). When the five elected candidates each reach the quota (505 votes in total) only 95 votes remain for the next highest candidate. If the quota had been 100 (only 1/6 of total) then the top six candidates could all reach this quota.
The first step is to count the number of first preference “1” votes for each candidate. All candidates that have reached the quota with first preferences are declared elected after “count 1” and withdrawn from the counting process before “count 2” commences.
All votes received by an elected candidate in excess of the quota (the surplus) will be distributed to the continuing candidates (at a later count) according to the preferences indicated on each ballot paper.
|Surplus = elected candidate's total votes – the quota|
It is important to understand that ballot papers and votes are different. Ballot papers are the medium from which candidates receive votes. The original value of a ballot paper is 1 vote; however, this can change during counting. To distribute surplus votes the parcel of ballot papers used are given a new (reduced) value.
The new ballot paper value for transferring the surplus (transfer value) is calculated as follows:
|(truncate to six decimal places)|
|Number of ballot papers in the last parcel|
A simple example:
If at the beginning of counting, a candidate (Jenny) receives 250 first preference votes and the quota is only 200 then:
If Justin then receives 100 of Jenny's 250 ballot papers he gains a further 20 votes (100 * 0.2 = 20 votes)
If a candidate is elected on first preferences, the next thing to do is to use all of his/her ballot papers to distribute the surplus votes as discussed above.
When more than one candidate is elected with a surplus, each surplus is distributed as separate counts in order of election.
Only the last parcel of ballot papers received by the elected candidate are used to distribute a surplus.
When elected at count 1, all first preference ballot papers are used (as seen in the simple example above). If elected at count 9, only the ballot papers received at count 9 are used.
Once all surpluses have been distributed, the candidate with the fewest total votes is declared excluded, withdrawn from the counting process and all of his/her ballot papers are redistributed to continuing candidates.
The exclusion of a candidate can take several counts to complete. When a candidate is excluded, ballot papers are passed on to continuing candidates at the same transfer value they were received by the excluded candidate. All ballot papers with the same transfer values are distributed as a new count.
After each count, each continuing candidate’s total number of votes is recalculated. Where a continuing candidate reaches the quota, he/she is declared elected and withdrawn from the counting process before the next count commences.
Once an exclusion is completed, the surplus of any candidate elected during that exclusion is distributed. Otherwise, again the continuing candidate with the fewest total number of votes is excluded.
The two processes of distributing surpluses and excluding candidates continues until all vacancies are filled. For House of Assembly elections, the scrutiny stops as soon as five candidates are declared elected.
It is common that the last member is elected without reaching the quota. In some cases, the last two members have been declared elected without reaching the quota.
If some ballot papers do not include a preference for every candidate, it is possible to be elected without reaching the quota. If a distributed ballot paper does not have a preference for any of the continuing candidates, it will drop out of the count and the vote it carries is declared "exhausted".
The number of exhausted votes usually increases quickly towards the end of the counting process as fewer candidates remain. The greater the number of votes exhausted, the more likely the last elected candidate will not reach the quota.
The ballot papers instruct the voter to mark a preference for all candidates to reduce the number and impact of exhausted votes.
There are two small differences. For Tasmanian Local Government elections, the number to be elected varies (depending on the election), the initial transfer value is 1 and all votes are calculated to 2 decimal places to reduce the loss of votes by fraction.
Enjoy this animation - a light-hearted look at the Hare-Clark electoral system.
In the lead up to the 2018 State Election the ABC education team asked Commissioner, Andrew Hawkey, to explain how the Hare-Clark counting system works, its history and why it's important for Tasmania.