Countback is a common term for the method Tasmania’s Hare-Clark electoral system has used for filling casual vacancies in the House of Assembly since 1917. Countback is also used for:

This principle, used in the cases above, is that the candidate elected to fill a casual vacancy is, of all the consenting candidates that were not elected for the electorate of the vacating candidate at the general election that elected that vacating candidate, the candidate that receives, at a re-examination by the Electoral Commission of the quota of votes that elected the vacating candidate, after successive distribution of preferences of excluded candidates, an absolute majority of votes. See Tasmania’s parliamentary website article on countback.

This principle ensures that the people that fill casual vacancies, unlike the unelected party appointees that fill casual vacancies by party appointment in the Senate, under Section 15 of the Australian Constitution, or in all mainland Legislative Councils except Western Australia’s, have all been directly elected by the people. Countback was enacted after John Humphreys urged it in his 1915 visit to save STV.

The only means provided for filling Hare-Clark vacancies in Tasmania’s House of Assembly before 1919 was a poll to elect one person by the whole electorate, which was obviously inconsistent with the PR method used at the General Election. Countback also usefully increases voters’ choices, as it encourages parties to nominate more candidates than just the bare minimum number from their party that they believe will be elected. removed that inconsistency.

If a by-election poll were to be held for the whole electoral district for just the vacated seat, all the voters that had originally elected the remaining representatives would be voting, and would massively outnumber the voters that had lost the representative they had elected.

One common criticism of countback is that the candidates often elected received far fewer first preference votes at the original election than some candidates at that election that were elected neither then nor at the countback. That criticism totally misses the point that countback is, and should be, totally confined to implementing the wishes of the electors whose representative has vacated the seat. If a countback system is in place, candidates seek like-minded fellow candidates to stand with them so that their voters can be asked to give their next preferences to those candidates so they will be available as replacements if the elected candidate has to vacate his or her seat. Sometimes that like-minded candidate will be actually elected instead of the person that expected to be elected, but that is solely a result of voters being given a wider choice and using it as they see fit.

A second common criticism of countback is that it is dependent on the ballots of those voters that were enrolled at the time the election at the start of the term in question was held, and that it excludes extra enrolments since then. The criticism unfortunately ignores the importance – for equity, balance and consistency – of having all the representatives for the term in question representing the same balance of views that were set up at the time of the main election. If it is so important that one of the representatives should represent later electors just because the predecessor has vacated his or her seat, all the other continuing representatives should also face election every time there is any vacancy, but that would obviously be a disruptive and haphazard approach.

A third, less common, criticism is that countback rules should be changed so that countback does not confine its examination of the votes cast at the preceding poll to the quota of votes that elected the vacating candidate, but instead goes beyond that to include the ineffective residue of votes at that poll that did not form part of any quota, and was, by definition, slightly smaller than the Droop quota used in modern PR systems. This criticism appears to be motivated by a belief that those voters – who were the only voters that had no effect on the outcome at the preceding poll – should be allowed to participate in the outcome of the countback. Unfortunately, that belief is inconsistent with countback’s basic principle, which is that the replacement for a vacating person should be based solely on the vote of the voters that originally elected that person, so the PRSA regards this claim as a misconception.


  • Tasmania’s current consolidated Electoral Act 2004 (No. 51 of 2004) replaces its Electoral Act 1985, which was the first consolidation made since the original Electoral Act 1907 (7 Edw. VII No. 6). Scrolling down below shows extracts relating to COUNTBACK from the Electoral Act 1985. Section 231 of that Act, whose effect is continued in Section 231 of the 2004 Act, provides for countback.
  • Section 233 of the 1985 Act, whose effect is continued in Section 232 of the new and current Act, was introduced to give the Parliamentary Leader of a Party certain choices if there is no continuing candidate available from that Party, but such a case has not arisen since countback was introduced in 1918. Access Tasmania’s official election reports, which detail Assembly countbacks from 1942 onwards.
  • View the atypical countback scrutiny in Tasmania that first elected Dr Bob Brown.
  • View the counting sheets of a Victorian and recent Tasmanian municipal countbacks.
  • View the helpful and detailed explanation of countback procedure by the ACT Electoral Commission.
  • View the Victorian Electoral Commission explanation of countback, and a letter about a common misconception.Tasmanian Electoral Act 1985