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Single transferable vote

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File:STV GVT.gif
This STV ballot for the Australian Senate illustrates group voting tickets. Voters can either rank every candidate individually or use their preferred party's preferences by voting "above the line."

The Single Transferable Vote, or STV, is a preferential voting system designed to minimise wasted votes and provide proportional representation in multi-candidate elections while ensuring that votes are explicitly for candidates rather than party lists. STV systems achieve this by initially allocating an individual's vote to their most preferred candidate and then subsequently transferring unneeded or unused votes after candidates are either elected or eliminated according to the voter's stated preferences.

When promoted as a proportional representation method in multi-party multi-seat elections, STV methods are generally known as Proportional Representation through the Single Transferable Vote or PR-STV. In Australia, it is known as the Hare-Clark Proportional method, while the same system used federally with parties able to indicate preferences is called simply STV. In the United States, STV is sometimes called choice voting. When STV methods are applied to single-seat elections, they simplify to instant-runoff voting and have different proportionality implications for a similar ballot due to the existence of only one winner.

Voting

Voting in STV is done with the goal of seeing that each elected representative has a number of distinct voters preferring one over other, unelected candidates. To ensure this, excess and unused votes from winning and losing candidates are transferred to remaining candidates according to the voter's preferences.

This method is sometimes approximated in elections among schoolchildren; the children line-up behind the candidate of their choice until enough members have a long enough line behind them. Since the children would all know that each candidate only needs a certain number of classmates' votes to be elected, those arriving last in line for a candidate who already has enough votes would choose to not waste their vote and instead move to another line to help someone else to win. Likewise, those children whose candidate obviously could not win would move to another line, and so on, until all the representatives are chosen.

File:Rankballotnumber2.gif

This process is automated in STV by use of the preferential ballot, a method for determining how to transfer votes, and a derived quota for determining winners. Each winning candidate represents a single quota's worth of votes analogous to the children lined up behind him, and voters are in turn automatically lined up and transferred according to how their preferences are listed on their ballots. Wasted votes, those that go to non-winning candidates or candidates that have already won, are therefore effectively minimized in STV systems, simultaneously minimizing the number of unrepresented voters and providing a degree of proportionality. Depending on the method of STV used and the preference distribution of the voters, these wasted votes can either be completely localised within a small portion of the electorate (less than one quota) or fractionally spread out amongst a larger share (who have portions of their votes transfer). Importantly, the more winners there are in a single constituency, the fewer votes that may be wasted under STV and therefore the more proportionate the outcome will be.

The preferential ballot

Voters in a Single Transferable Vote election cast a preferential ballot that is a ranked, ordinal listing of their preferred candidates. Voters in STV elections have a significant incentive to list their preferences honestly, as doing so improves the likelihood of the voter attaining representation amongst the winning candidates (see tactical voting, below).

Many STV systems allow voters to give a partial list of preferences by only ranking a subset of the candidates, however this leads to the possibility of exhausted votes, where a vote, or portion of a vote, is unable to be transferred because there are no more candidates indicated on the exhausted ballot. To prevent exhausted ballots, some STV systems instead require voters to give a complete ordering of all the candidates in an election. However, when there is a large set of candidates this requirement may prove burdensome and can lead to voters ranking their final choices arbitrarily when they lack strong opinions ("Donkey voting"). To facilitate a complete ballot, some STV systems may provide the voter with the option of using group voting tickets rather than having to completely identify individual preferences.

Counting the ballots

The Droop Quota
Main article: Counting Single Transferable Votes

The quota (sometimes called the threshold) is the number of votes a candidate must receive to be elected. Votes are assumed to go to the top preference first, and are then transferred from eliminated candidates and the surpluses of winners until enough candidates meet the quota to fill the number of seats. To avoid unnecessary counting, candidates may instead be eliminated until the number of seats left to fill is the number of remaining candidates. This approach becomes necessary if ballots are allowed to be exhausted, as it then becomes possible for an insufficient number of candidates to reach the quota if the exhausted votes are numerous enough to fulfil a quota instead.

STV systems differ in how they transfer votes as well as the exact size of the quota used for determining winners. The Droop quota, the most common, minimizes the size of the quota while still maintaining the condition that no more candidates can reach a quota than there are seats to be filled. While this still leaves nearly a quota's worth of votes unallocated (wasted), transferring these votes would not alter the eventual outcome. For example, Meek's method, the method of transferring votes adopted in the New Zealand STV system, utilizes a computer to evenly transfer portions of excess votes from winning candidates until they barely satisfy the quota, thereby taking into account transfers to already elected candidates. Meek's method also dynamically adjusts the quota during the counting process of the election, lowering it slightly to take account newly exhausted votes. In Meek's method, initially different ballots that express the same preferences after particular candidates are eliminated are weighted exactly the same - there is no penalty for ballots arriving at a candidate in an earlier round than others.[1]

An example

# x x x x x x x x x x
x x x x 		x x x x x x
1st Orange Tangerine Chocolate Chocolate Strawberry Candy
2nd Tangerine Orange Strawberry Candy
3rd Candy Strawberry

Suppose a food election is conducted to determine what to serve at a party. There are five candidates, three of which will be chosen: oranges, tangerines, chocolate, strawberries, and candy. The 20 guests at the party have the preferences marked on their ballots in the table at the right, with each ballot being represented by a colored x. Note that in this example it is not needed for some of the voters to indicate a complete preference list, however in a larger election with more candidates the value of ranking additional preferences to the voter increases.

Using the Droop quota, with 20 voters and 3 winners the number of votes required to win is therefore:

Note that if the quota were exactly 1 vote less, it would become possible for 4 candidates instead of 3 to fulfill it.


Candidate: Orange Tangerine Chocolate Strawberry Candy
Round 1 x x x x x x x x x x
x x x x
x x x x 		x x Chocolate is elected, since chocolate has more votes than the quota.
Round 2 x x x x x x x x x x
x x 		x x x x
x 		x x x Chocolate's surplus votes transfer proportionately to strawberry and candy according to the chocolate voters' second choice preferences. Tangerine is eliminated since no new candidates meet the quota and tangerine has the least support.
Round 3 x x x x
x x 		  x x x x
x x 		x x x x
x 		x x x Tangerine's votes transfer to their second preference, orange, causing orange to reach the quota and be elected. Orange barely meets the quota, and therefore has no surplus to transfer.
Round 4 x x x x
x x 		  x x x x
x x 		x x x x
x 		x x x Neither of the remaining candidates meets the quota, so candy is eliminated. Strawberry is the only remaining candidate and so wins the final seat.

In this sample election, the number of wasted votes is 4: the three unsuccessful votes for candy in the final round that did not elect a candidate, plus one less than the difference between strawberry and candy's votes in the final round (5 and 3, respectively). This is 4/20, or 20% of all the votes cast.

History

The concept of transferable voting was first proposed by Thomas Wright Hill in 1821. The system remained unused in real elections until 1855, when Carl Andrae proposed a transferable vote system for elections in Denmark. Andrae's system was used in 1856 to elect the Danish Rigsdag, and by 1866 it was also adapted for indirect elections to the second chamber, the Landsting, until 1915.

Although he was not the first to propose a system of transferable votes, the English barrister Thomas Hare is generally credited with the conception of Single Transferable Voting, and he may have independently developed the idea in 1857. Hare's view was that STV should be a means of "making the exercise of the suffrage a step in the elevation of the individual character, whether it be found in the majority or the minority." In Hare's original STV system, he further proposed that electors should have the opportunity of discovering which candidate their vote had ultimately counted for, to improve their personal connection with voting.[2] This is unnecessary in modern STV elections, however, as an individual voter can discover how their vote was ultimately distributed by viewing detailed election results.

The noted political essayist, John Stuart Mill, was a friend of Hare and an early proponent of STV, praising it in his essay "On Representation." His contemporary, Walter Bagehot, also praised the Hare system for allowing everyone to elect an MP, even ideological minorities, but also added that the Hare system would create more problems than it solved: "[the Hare system] is inconsistent with the extrinsic independence as well as the inherent moderation of a Parliament - two of the conditions we have seen, are essential to the bare possibility of parliamentary government."[3]

STV spread through the British Empire, leading it to be sometimes known as British Proportional Representation. In 1896, Andrew Inglis Clark was successful in persuading the Tasmanian House of Assembly to be the first parliament in the world elected by what became known as the Hare-Clark system, named after himself and Thomas Hare.

Meek's version contained the innovation that electors could rank preferences equally, but this option has not been used.[4]

File:Propo-bondage.jpg
This propaganda image, created for a campaign to promote STV in Scotland, characterizes votes under Scotland's plurality system as being tied up in bondage.

Issues

A frequent concern with STV among electorates considering its adoption is its relative complexity compared with plurality voting methods. For example, when the Canadian province of British Columbia held a referendum on adopting the Single Transferable Vote in 2005, according to polls a majority of "no" voters gave their reason as "wasn't knowledgeable" when they were asked why, specifically, they voted against STV.[5]

However, as with all voting systems, once STV is understood there remain a number of areas of controversy surrounding its use. In particular, arguments for and against proportional representation in general are frequently referenced in debates among electorates considering STV, however the specific implications of a particular STV system can be examined as well.

Proportionality

The outcome of voting under STV is proportional within a single election to the collective preference of voters, assuming voters have ranked their real preferences. However, due to other voting mechanisms usually used in conjunction with STV, such as a district or constituency system, an election using STV may not guarantee proportionality across all districts put together. Differential turnout across districts, for example, may alter the impact of individual votes in different constituencies, and rounding error associated with a finite number of winners in each constituency may throw up anomalous results. The New South Wales Legislative Council, where the whole state votes as a single electorate for 21 members, produces results that are proportional to the final allocation of preferences. In STV elections to the Australian Senate, states with vastly different populations have the same number of seats, and so while the results for individual states are proportional, the nationwide result is not, giving greater voting power to individual voters in less populated states; however, this lack of proportionality is derived from malapportionment rather than any deficiency in STV.

STV provides proportionality by transferring votes to minimise waste, and therefore also minimises the number of unrepresented voters. In this way STV provides Droop proportionality - an example STV election using the Droop quota method for 9 seats and with no exhausted preferences would guarantee representation to every distinct group of 10% of the voters, with at most only 10% of the vote being wasted as unneeded excess. Unlike other proportional representation methods employing party lists, voters in STV do not explicitly state their preferred political party. One common method of estimating the party identification of voters is to assume their top-preference on their ballot represents a candidate from their preferred party. This method is made more complicated by the possibility of independent candidates and of cross-party voting.

Nevertheless, failures to produce partisan proportionality exactly analogous to the party affiliations of top choice candidates as occurs in list PR elections can be controversial. For example, in Malta in 1981 the party winning more than half the votes won less than half the seats, resulting in a constitutional crisis: see below. Similarly the Northern Ireland elections in 1998 led to the Ulster Unionists winning more seats than the Social Democratic and Labour Party, despite winning a smaller share both of first-preference votes and of votes after transfers.

Tactical voting

The single transferable vote eliminates much of the reason for tactical voting. Voters are "safe" ranking candidates they fear may not be elected, because their votes will be transferred after they are eliminated. Similarly, voters are also "safe" voting for a candidate they believe will receive overwhelming support, because their votes will then get reallocated to their next preference, though with less than the value of a full vote. However, the Gibbard-Satterthwaite theorem states that tactical voting is possible in any deterministic voting system where any candidate can win, and that STV is no exception.

Tactical voting is chiefly accomplished in STV by making assumptions about the other voters. A preferred popular candidate can be assumed to win and thus ranked lower on a tactical voter's ballot, allowing the voter to give more weight in transfers to his second-choice candidates (and, implicitly, giving fellow supporters of the popular candidate less weight.) This is particularly effective in the older STV systems still used in many countries that prevent elected candidates from receiving additional votes, as in that case none of the tactical vote is diluted on the already winning candidate. Under such old systems, a voter may even rank a non-preferred candidate that is assumed to lose first in order to increase the chances of his vote arriving late. This method of tactical voting is much less effective in the New Zealand STV system using Meek's method, however, as votes receive the same fractional weighting regardless of when they arrive at the successful candidate.

Though still theoretically possible, figuring out how to successfully vote tactically in modern STV systems by exploiting the non-monotonicity in this way can be computationally difficult. It is NP-hard to determine whether there exists an insincere ballot preference that will elect a preferred candidate, even in an election for a single seat.[6] This makes tactical voting in STV elections vastly more difficult than with other commonly-used election methods. Importantly, this resistance to manipulation is inherent to STV and does not depend on hopeful extraneous assumptions, such as the presumed difficulty of learning the preferences of other voters. Furthermore, it is also NP-hard to determine when an STV election has violated the monotonicity criterion, greatly reducing the likelihood that the electorate will know if even accidental tactical voting has occurred. As a consequence, the difficulty of tactical voting in STV elections increases sharply as the number of voters, candidates, and winners increase. This gives an incentive for larger electoral districts other than their increased proportionality, since particularly small electoral districts may have few enough candidates to make tactical voting feasible.

Of special note is that voters have a real incentive to list their preferences honestly in STV, as it is the best strategy for securing representation if tactical voting is either impractical or impossible. This is frequently the case in large electoral districts, as successful tactical voting (when possible) requires both nearly perfect information about how others are voting and the computation of a virtually unsolvable math problem. Since tactical voting in STV works by effectively substituting one's own alternate preferences for transfers with other supporters of the same candidate, the effectiveness of tactical voting is greatly reduced when other supporters of preferred candidates have similar second-choice preferences. Although there is no way to completely prevent tactical voting by hiding support for preferred candidates, the tactical voter carries the significant danger of his assumption's about the popularity of his preferred candidate being wrong, risking his most preferred candidate losing because of his miscast tactical vote. This contrasts heavily with non-proportional, plurality-based systems, where there is both tremendous incentive and ability to vote tactically in order to avoid the spoiler effect.

Effects on factions and candidates

File:Sweet-propo.jpg
This campaign poster highlights STVs tendency to provide descriptive representation according to each voter's individual preferences by making a comparison with diverse flavors of candy.

The use of STV may reduce the role of political parties in the electoral process and corresponding partisanship in the resulting government. Unlike proportional representation systems employing party lists, voters in STV are not explicitly constrained by parties even when they do exist; voters may ignore candidate party labels and mix their preferred candidate rankings between parties. Similarly, candidates may achieve electoral success by obtaining a quota of voters not generally within their own party, perhaps by winning transfers from moderates or by championing a specific issue contrary to party doctrine. Unlike List PR, STV can be used in elections in organizations without any political parties at all, such as in trade unions, clubs, and schools.

Some STV variations, however, may encourage the role of political parties and actually strengthen them. In Australian Senate elections, where a combination of large districts, mandatory complete ballots, and compulsory voting results in the near 95% usage of partisan group voting tickets, political parties gain significant power in determining election results by adjusting the relative ordering of their tickets.

Successful campaign strategy in STV elections may differ significantly from other voting systems. In particular, individual candidates in STV have little incentive for negative campaign advertising, as reducing a particular opponents ranking among voters does not necessarily elevate one's own; if negative campaigning is seen as distasteful by the voters, the practice may even prove harmful to the attacking candidate. Conversely, in order to avoid elimination in early counting rounds by having too few first place votes, candidates have a significant incentive to convince voters to rank them explicitly first as their top preference, rather than merely higher. This incentive to attain top preferences, in turn, may lead to a strategy of candidates placing greater importance on a core group of supporters. Avoiding early elimination, however, is usually not enough to win election, as a candidate must still subsequently win enough votes on transfers to meet the quota; consequently, strategies which sacrifice wide secondary support in favor of primary support amidst a core group may ultimately fail unless the group is particularly large.

There are also tactical considerations for political parties in the number of candidates they stand in an election where full ballots are not required. Standing too few candidates may result in all of them being elected in the early stages, and votes being transferred to candidates of other parties. Standing too many candidates might result in first-preference votes being spread too thinly amongst them, and consequently several potential winners with broad second-preference appeal may be eliminated before others are elected and their second-preference votes distributed. This effect is amplified when voters do not stick tightly to their preferred party's candidates; however, if voters vote for all candidates from a particular party before any other candidates and before stopping expressing preferences, then too many candidates is not an issue. In Malta, where voters tend to stick tightly to party preferences, parties frequently stand more candidates than there are seats to be elected. Similarly, in Australian Senate elections, voters also tend to vote along party lines due to the relative ease of selecting a party's declared preferences rather than individually casting their own complete list.

Voting system criteria

Academic analysis of voting systems such as STV generally centers on the voting system criteria that they pass. No system satisfies all the criteria described in Arrow's impossibility theorem: in particular, STV fails to achieve independence of irrelevant alternatives (like most other vote-based ordering systems) as well as monotonicity. Failure to satisfy independence of irrelevant alternatives makes STV slightly prone to strategic nomination, albeit less so than with plurality methods where the spoiler effect is more pronounced and predictable. Non-monotonicity, in turn, makes it possible under some circumstances to elect a preferred candidate by reducing his position on some of the ballots; by helping elect a candidate who displaces the preferred candidate's main rival, a voter may cause the preferred candidate to profit from transfers resulting from the rival's defeat. STV fails the participation criterion which can result in a more favorable outcome to an STV voter by not voting at all. However, STV satisfies the Non-compulsory support criterion. A voter who truncates a candidate off the ballot does not harm a ranked candidate, nor is another truncated candidate helped on the ballot.

STV is also susceptible to the Alabama paradox: if a candidate is elected in an n seat constituency, she may not be elected in the same constituency with n + 1 seats even when voters express exactly the same preferences. This is due to the use of quotas; list PR by a largest remainder method is similarly affected, though a highest averages method is not. Intuitively, a candidate who was elected largely because of transfers from two similar groups (neither obtaining a quota) may not be elected when the number of winning candidates increases, as both groups would instead get their preferred candidates elected (with the new, smaller quota) rather than automatically compromising on their mutual second choice as their votes transfer.

Some modifications to STV have been proposed in order to pass monotonicity and other criteria. The most common method of proposed modification to STV is to alter the order in which candidates are eliminated: theoretically, a candidate who ranked second on every ballot could be the first candidate eliminated even if he is a Condorcet winner. Meek noted this problem in proposing his variation of transferring votes to nearly eliminate tactical voting in STV, however Meek himself did not propose a method for satisfying the Condorcet criterion. Other theorists have proposed further refinements of STV, such as using a Condorcet method to rank candidates for elimination order. Some of these modifications alter STV in a way such that it no longer reduces to instant-runoff voting when applied to a single seat but instead reduces to some other single winner system, such as a Condorcet method.

See also: CPO-STV, Quota Borda system

District size

Another issue commonly considered with STV elections is the size of the voting districts in terms of the number of candidates elected and, to a lesser extent, the total size of the body being elected. In STV and other proportional representation systems, a larger number of candidates elected results in a smaller number of wasted votes and subsequent rounding error, leading to a more proportionally representative outcome based on the preferences of the voters. For this reason, larger electoral districts can also significantly reduce the effects of gerrymandering; because gerrymandering relies on wasted votes to award the "last seat" in each district, proportional representation systems such as STV with larger multimember districts are intrinsically more difficult to gerrymander.[7] Larger districts can also make for significantly harder tactical voting: since the problem of making correct assumptions about other voter's behavior and rearranging one's tactical ballot is NP-Hard, the difficulty of tactical voting increases sharply as the number of candidates grows. Some STV elections make use of districts with the number of seats available as small as three, however there is no theoretical upper limit to the size of districts in STV, and they may not even be needed at all: Thomas Hare's original proposal was for a single, nationwide district.

However, because STV is proportional, larger elections also reduce the support a candidate requires to become elected as a percentage of the district. With 9 candidates, for example, any with 10% electoral support may win a seat, whereas with 19 candidates only 5% popular support is required to be in the government. Because of this, proportional representation methods such as STV can implicitly allow for the election of particularly small minorities provided they secure a quota's worth of votes. The potential admission of small voting minorities into the government, perhaps including political extremists, can be quite controversial even though they would occupy only an equivalently small proportion of the government once elected. Other proportional representation methods attempt to avoid the election of small political minorities by imposing partisan threshold requirements, such as the "5% rule" in Germany's Mixed Member Proportional system. While impossible at the national level, such a threshold requirement could be approximated in STV on a per-district basis by limiting the number of seats to 19 (and therefore making the quota one more than 5% of the vote). Larger districts and the implicit larger number of candidates also increase the difficulty of giving meaningful rankings to all candidates from the perspective of the individual voter, and may result in increased numbers of exhausted ballots and reliance on party labels or group voting tickets.

Vacancies

When compared with other voting methods, the question of how to fill vacancies which occur under STV can be difficult given the way that results depend upon transfers from multiple candidates. There are several possible ways of selecting a replacement:

Countback

The countback method is used in Tasmania, Malta, and Cambridge, Massachusetts. A new representative is selected by using the data from the previous election. The candidate who held the seat is eliminated, and a new election result is obtained by transferring votes from the now unrepresented voters. Importantly, a clone of the replaced representative would be guaranteed to win the vacated seat. An interesting consequence of the countback method's use of existing ballots for selecting replacements is that the results are often known before the vacancy actually occurs, potentially influencing the circumstances which create the vacancy in the first place.

Although the countback method is designed to select a replacement representing the same group of voters who elected the original candidate, it remains possible that no similar candidates remain on the ballot. In 1985 the Tasmanian parliament amended the electoral act to allow true by-elections if no candidates of the same party as the outgoing representative remained on the ballot; in this circumstance the party may request that a by-election be held, however this has not yet happened.

Countback methods vary by whether or not wasted and exhausted ballots are additionally used during the countback. The effect this has on the result of the countback depends on the differences in the next preferences of voters; if there exists a true clone in the ballots, there should be no effect in this change. Moreover, in STV systems that use exhausted ballots during countbacks, it becomes theoretically possible that the order of multiple resignations will affect whom the ultimate replacements are - this is a consequence of the non-independence of irrelevant alternatives discussed above. Additionally, if ballots are allowed to be exhausted in the election, then by either method it remains possible that the chosen replacement will only meet a fraction of a quota of voters; when this fraction is particularly small, and therefore no similar candidates remain on the ballot, election rules may call for a different method of filling the vacancy to be used.

Appointment

Another option is to have a head official or remaining members of the elected body appoint a new member to fulfil the vacancy. In Australia, for example, the state legislatures appoint replacements members to the Australian Senate, now done at the suggestion of the party of the outgoing senator. Before this rule, disputes over Senate vacancies contributed to the Australian constitutional crisis of 1975, ultimately resulting in a 1977 amendment to the Constitution of Australia to provide that the legislature must elect a member of the same party as the outgoing senator. Vacancies in the New South Wales Legislative Council are filled in a similar way by a joint sitting of both the legislative council and assembly.

By-election

A third alternative to fulfil a vacancy is to hold a single-winner by-election (effectively instant-runoff), as happens in the Republic of Ireland; this allows the parties to choose new candidates and all voters to participate, but often leads to the most popular party picking up an extra seat. This is because the winner of a by-election typically represents a large group of voters, whereas the vacated member only represented a particular quota's worth.

Use of STV around the world

Australia

Australia uses two forms of STV, usually referred to within Australia as the Hare-Clark System and STV. Both systems require voters to rank all of the candidates on the ballot, eliminating the possibility of exhausted votes.

The Hare-Clark System is used in Tasmania's House of Assembly and the Australian Capital Territory (ACT) Legislative Assembly. This is essentially the system described above using the Droop quota (not the Hare quota), but candidates' placements are randomised by Robson Rotation rather than grouped by party.

STV or proportional voting is the system used in the Australian Senate and the Legislative Councils of New South Wales, Victoria, Western Australia and South Australia. This system is counted in the same way as in Hare-Clark, but group voting tickets are used.

Each form has its pros and cons. The Hare-Clark system with Robson Rotation is advocated on the grounds that voters know who they are voting for as they must fill all their preferences, that each party's candidates compete with each other and the effect of 'donkey voting' is reduced because of the randomised ordering. The alternative system is advocated on the grounds that informal voting is reduced because only one number need be written; on the other hand, it greatly increases the potential for tactical voting by parties as they both have more information about the ballots and direct control of a larger percentage of the vote. In the Australian Senate elections, nearly 95% of voters use the group voting tickets instead of ranking their own preferences.

Canada

STV was used in Canada in the Calgary and Edmonton ridings of the Alberta province from 1926 to 1955. Other Alberta ridings had the option of using STV or First-past-the-post (FPTP) , and alternated between the two, however all ridings reverted to FPTP in 1955.

Provincial elections in Manitoba were conducted by STV from the 1920s until 1958. The city of Winnipeg elected ten members in this manner, while all other constituencies elected one member by instant-runoff voting. Civic elections in Winnipeg were also conducted by STV.

The Citizens' Assembly on Electoral Reform established by the British Columbia government surprised many when it developed an STV electoral model called BC-STV and recommended it to the electorate.[8] In the ensuing electoral reform referendum held on May 17, 2005, BC-STV achieved 57.7% Yes support. This did not give it the 60% province-wide support set by the government for the referendum outcome to be automatically binding, though the simple majorities in 77 ridings (of 79) far exceeded the 48 ridings that was also a requirement. Due to the evident support for electoral reform, the re-elected Liberal government announced in the Throne Speech on September 12th that the public of British Columbia would get a second referendum on STV in November 2008. In the interim, the Electoral Boundaries Commission will be convened and instructed to design new boundaries for both FPTP and STV with a final report coming out in the spring of 2008. Both supporting and opposing sides of the referendum campaign will recieve government funding to help educate the public in time for the November 2008 referendum, after which the winning system will be used for the next provincial election on May 12th 2009.[9]

Ireland (Republic)

STV is used in the Republic of Ireland for all elections. However, Irish presidential elections and most by-elections elect only one candidate and so reduce to instant-runoff voting. The Irish Constitution specifies a minimum size of 3 seats for Dáil constituencies; the current maximum is 5. Senate panels, however, have up to 11 seats.

Although efforts to introduce STV across the UK had been abandoned, STV was adopted for use in local elections in Sligo in 1918, while Ireland was still a part of the UK, and then extended to all Irish local elections. STV was then used in the Irish elections of 1921, and subsequently adopted for all elections by the new Irish Free State in 1922. Attempts by Fianna Fáil governments to replace STV with FPTP were defeated in referendums in 1959 and 1968.

Malta

STV applies for all elections in Malta. However, top-up seats (similar to the additional member system) may be added in the national parliament to ensure that a party with a majority of first-preference votes wins a majority of seats. This was a response to the controversial election in 1981 when the Nationalist Party won 51% of the first-preference vote but the Labour Party won a majority of the seats.[10] Some subsequently accused Labour of having gerrymandered the 5-seat constituencies: 8 had narrowly split 3:2 in its favour, while 5 had more widely split 3:2 in favour of the Nationalists. The top-up rule was also invoked in 1987 for the benefit of the Nationalists and in 1996 for the benefit of the Labour Party.

The Maltese electorate largely does not take advantage of the cross-party voting opportunities provided by STV. Almost all voters give preferences to all the candidates from one of the two major parties, but do not give preferences to candidates from the other party. Third parties, meanwhile, get minimal support. The effect of this voting pattern is similar to a tight two-party open list PR system simultaneously using STV within each party to decide its representatives whilst using the indicated first preference candidate's party as the voter's preferred party. Because of the transfer behaviour of the voters, each party can stand many more candidates than there are winners in total without being adversely affected. Strangely, some candidates stand and are elected in more than one constituency, leading to vacancies filled by countback.

New Zealand

New Zealand used STV for the first time for district health board and some local authority elections in October 2004.[11] New Zealand has chosen STV by Meek's method. In recent elections, ballot papers contained ballots for multiple local government elections, some of which were conducted by single-winner FPTP, some by plurality at large, and some by STV. Due to low voter turnout, the high number of invalid votes and the long time taken for the result to be declared, the Justice and Electoral Committee of the New Zealand Parliament has under taken an inquiry into the use of STV in New Zealand.

United Kingdom

In 1917, the Speaker's Conference in the United Kingdom advocated the Single Transferable Vote for 211 of the 569 constituencies in Britain and instant-runoff for the rest. Although the House of Commons voted in favour of the proposals five times, the House of Lords continually rejected it until the nationwide effort was ultimately abandoned in parliament.[12]

STV was adopted for Irish local elections, for the Irish elections of 1921 and for the Northern Ireland general election, 1925 but was abolished in Northern Ireland in the late 1920s by the devolved parliament. It was reintroduced there after Direct Rule in 1973, and remains in use for local, Assembly and European elections, though not for elections to the House of Commons at Westminster.[13]

England does not use STV for public elections, though it had been in use for some university constituencies before 1945. In Scotland, after the passage of the Local Governance (Scotland) Act on June 23, 2004, all local governments will be using STV to elect their councillors in 2007.[14] In Wales, the Richard Commission recommended changing the electoral system for the National Assembly for Wales to the Single Transferable Vote in March of 2004. However, in the white paper Better Governance for Wales published on June 15, 2005, the UK Government rejected Richard's recommendation to change the electoral system.

United States

STV enjoyed some popularity in the United States in the first half of the 20th Century. Twenty-two American cities have used STV for local elections. Notably, New York City employed STV in 1936 as a method for breaking the corrupt political machine of Tammany Hall dominating the city. After World War Two, harsh campaigns against STV were carried out after women, blacks, and political minorities such as Communists began winning seats, even though they only constituted a minority group in government. After STV's removal and subsequent reversion to FPTP in New York in 1947, the Democratic Party immediately regained near unanimous control of municipal elections with Tammany Hall quickly returning to political dominance until its ultimate downfall in the mid 1960s.[15]

Currently the only official governing bodies that use STV to elect representatives are the City Council and School Committee of Cambridge, Massachusetts. The community school boards of the City of New York continued to use STV until the school boards themselves were abolished in 2002. The city of San Francisco recently considered multimember STV in a referendum, however this effort failed and the city instead uses districted instant-runoff.

Single Transferable Voting has become increasingly used at American universities for student elections. As of 2005, the schools of Harvard, Princeton, UC Berkeley, UC Davis, Vassar, Reed, and Whitman all use STV, and several other universities are considering its adoption.

See also: List of US cities that have used STV

NGOs

Many non-governmental organisations also use STV. Most Australian political parties, unions and peak business organisations use STV. All National Union of Students of the United Kingdom, Cambridge Union, and Oxford Union elections and those of their constituent members are under the system. It is used as well by ESIB – The National Unions of Students in Europe. It is used in several political parties for internal elections such as the British Liberal-Democrats and all the British Green Parties. It is also used to elect members of the General Synod of the Church of England. The UK Royal Statistical Society [16] uses STV with the Meek method to elect their council.

See also

References

  1. ^ Hill, I.D. (1987). "Algorithm 123 — Single Transferable Vote by Meek’s method".
  2. ^ Lambert & Lakeman (1955). "Voting in democracies". London : Faber, pg. 245.
  3. ^ Bagehot, Walter. "English Constitution".
  4. ^ Meek, Brian (1969). "A New Approach to the Single Transferable Vote". Voting Matters Issue 1. Translated to English in 1994.
  5. ^ Video postmortem on BC-STV referendum (British Columbia's version of STV).
  6. ^ Bartholdi, John J. III and Orlin, James B (2003). "Single Transferable Vote Resists Strategic Voting".
  7. ^ Whyte, Nicholas. "A note on Gerrymandering". Accessed Aug 12, 2005.
  8. ^ Citizens' Assembly on Electoral Reform. "News release: Assembly's recommendation to B.C." British Columbia, 24th October, 2004.
  9. ^ Bains, Camille. "STV supporters press for electoral reform despite referendum defeat". Canadian Press, May 18, 2005
  10. ^ Maltadata.com. "Elections in Malta: The Single-Transferable-Vote System in Action, 1921 - 2004". Accessed Aug 11, 2005.
  11. ^ New Zealand Department of Internal Affairs (2004). "STV - It's simple to vote". Accessed Aug 11, 2005.
  12. ^ Electoral Reform Society. "A Brief History of Electoral Reform". Accessed Aug 11, 2005.
  13. ^ CAIN "Introduction to the Electoral System in Northern Ireland" Accessed Sep 15, 2005.
  14. ^ Scottish Parliament (2004). "Local Governance (Scotland) Bill."
  15. ^ Prosterman, Dan. STV in New York. Accessed Aug 11, 2005.

Proponent Groups

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