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Representative government: the electoral systems - Theresa Reidy

26th May, 2022


At their core, electoral systems convert votes cast at elections into seats in parliament. This is the opening sentence of nearly every book ever written on electoral systems. But electoral systems do much more. Michael Gallagher and Paul Mitchell (2008) describe the electoral system as the ‘crucial link in the chain of representative democracy’ and Pippa Norris (1997) has argued that electoral system choice is one of the most enduring decisions that can be made within a political system.

Proportional Representation by the Single Transferable Vote (PRSTV) was the electoral system chosen for elections, North and South, at the foundation of the two separate political jurisdictions. Within a short number of years, PRSTV was rejected for use in Northern Ireland, and replaced with First Past the Post (FPTP) while PRSTV became one of the defining institutions of political life in the Free StateRepublic of Ireland. Importantly the two systems operated with very different logics and principles but yielded somewhat similar outcomes in their initial decades of operation. Variants of majoritarian style politics emerged both in Northern Ireland and the Free State despite theoretical expectations at least that PRSTV in the Republic would generate multipartyism and a more consensus style of politics. As society changed and political conditions evolved, PRSTV in the Republic proved itself an electoral formula that could reflect change while FPTP in Northern Ireland amplified underpinning divisions.

The vibrant field of electoral system scholarship has demonstrated concretely that the different families of electoral systems generate notable, and variable outcomes as happened in Ireland. The electoral system adopted can impact upon which citizens are represented and to what extent, the composition of the party system, common form of government and government durability. Matt Shugart (2008: 28) has also described how electoral system choice impacts upon the broader concerns of political science, such as ‘regime stability, democratic quality and management of ethnic conflict’. But indeed, as Moser and Scheiner (2012) have shown, political context also systematically shapes the effects of electoral systems. It is useful to unpack some of these points in a short review of electoral politics in Northern Ireland and the Free State.

As early as the nineteenth century it was understood that proportional systems generated more equal representation giving a closer relationship between the votes cast for a party and the seats it received but the accepted downside was this often meant political fragmentation with many political parties and unstable forms of government (i.e. coalition).

Majoritarian systems provided a more imperfect relationship between votes and seats, favoured two party politics but yielded stable majority governments.

These central propositions were formalised into theoretical models in the 1950s by the French political scientist Maurice Duverger (1954). Duverger classified party and government consequences as the ‘mechanical’ effects of electoral system choice. He also elaborated on the psychological effects of electoral systems and the ways in which political parties, candidates and voters behave in response to, and expectation of, how the electoral system operates. For example, it is difficult for small parties to succeed in plurality systems, thus there are limited incentives to create new parties. These are not ‘laws’ of political science but they are borne out in many cases. For example Arend Lijphart (1994) demonstrated that the effective number of parties is 2.0 in plurality systems and 3.6 in PR systems (see also Singer 2013).

Northern Ireland and the Irish Free State provide a fascinating comparative case study of the outcomes of different electoral systems in operation in neighbouring but substantially different polities. In the early decades, these two systems delivered unusually similar majoritarian politics with small numbers of parties and single party governments but they tracked in very different directions as the decades passed.

PR in Ireland

As John Coakley (1991) has documented, PRSTV was introduced in Ireland for selected constituencies under the Home Rule Act (1914), for local elections in Sligo 1918 and then latterly in 1919 for the whole country, and for parliamentary elections in to the Northern and Southern parliaments under the Government of Ireland Act (1920).

Interestingly the selection of PRSTV as the electoral system for Ireland was largely uncontroversial. Discussion of electoral reform was widespread in Great Britain in the late nineteenth century and momentum for change also took hold in Ireland. An Irish branch of the Proportional Representation Society was established and Basil Chubb (1992: 133) highlighted the attendance of Arthur Griffith at an early public lecture in 1911 as decisive in shifting Sinn Féin support in favour of the system. The representation of minority interests that was offered by PR persuaded Griffith that it could work effectively for the complex politics of pre-independence Ireland. Conn O’Leary (1961) also cites the widespread use of PR across new European democracies and the fact that it was not used in Britain as also being important indicators of why it was embraced by Sinn Féin. The only voices in opposition to PRSTV came from the Ulster Unionist side and their opposition was rooted in the view that the system was ‘unBritish’ (O’Leary 1979: 6).

There were strategic considerations at play in the thinking of the British administration and its support for PRSTV at elections in Ireland. It was persuaded the system could deliver representation for the Protestant minority on the island: the Anglo Irish in Southern Ireland and Ulster Unionists in Northern Ireland. Conn O’Leary (1979:8) has argued that the outcome of the 1918 general election in which nationalists swept the board using FPTP, reinforced support for PRSTV among British decision makers. He cites later newspaper coverage of the Sligo local elections that used PRSTV and the fact that Sinn Fein was pushed into second place, as important in persuading Southern Unionists that PR could deliver minority representation. The PR system also delivered representation for natio nalists in local electoral districts in Northern counties in 1919, in further evidence of its effectiveness for minority representation.

With the British administration onside and tacit support from nationalists, PRSTV emerged as the electoral system of choice for the parliaments in Northern Ireland and Southern Ireland in the Government of Ireland Act (1920), (Coakley 1991). PR was included in the Anglo Irish Treaty of 1921 and later transposed into the Free State Constitution.

Several histories that address the choice of PRSTV remark that it was selected at the time because it was the only version of PR then known to the negotiators (Gallagher, 2005: 513; Chubb, 1992) although Joe Lee (1989) notes that there were concerns expressed during the writing of the Free State Constitution that PR might lead to an excessive form of multipartyism and unstable government. Lee goes on to provide a long quote from Ernest Blythe from a later date on the same point. So while it may have been the case that STV was the only version of PR known at the time, some of its potential implications and consequences were considered.

The early PRSTV elections (especially in Southern Ireland, later the Free State) tell us little about the system. Electoral pacts and uncontested seats delivered pre-ordained outcomes. The first, what we might today term, ‘free and fair’ general election in the Free State was held in 1923. It used PR as mandated by the Free State constitution and STV as set out in the Electoral Act (Lee, 1985). The Dáil consisted of 153 TDs elected from 30 constituencies with district magnitudes between three and nine seats. Conn O’Leary (1979) described a keen contest with 375 candidates and the outcome was broadly proportional; four parties and two groups of independents (Unionists and non-party) were elected.

A minority single party government was installed, albeit one that was able to act as though it had a majority because of Anti-Treaty Sinn Féin abstention. Several new and splinter parties formed in the ensuing years reflecting one of Duverger’s psychological effects, that party entry is easier in a PR system. However, most failed to mount serious challenges at later elections and faded from politics or were absorbed into the existing parties. The first 1927 election substantially defined the party system with Fianna Fáil’s early performance setting the ground for its later dominance while the second election resulted in many of the early smaller parties losing seats they would not regain.

The effective number of elective parties, a measure of political fragmentation, was above four until the close of the 1920s when it dropped back to three. New party entry was again a feature in the 1940s but it was not until the late 1990s that fragmentation reached levels seen at the foundation of the state. The Republic of Ireland had a two and a half party system for most of the twentieth century, an outcome more commonly associated with a majoritarian electoral system. There were periods of electoral change but the Fianna Fáil- Fine Gael-Labour core always reasserted itself, that is until the early twenty first century where the evidence suggests that the system is mean-reverting no more!

In many ways, the Free State provided a rare inversion of Durverger’s proposition. It began with a multi-party system that Peter Mair (1970) described as polarised pluralism. It drifted towards a two and a half party system with more moderate pluralism from the 1930s to the early 1990s, when the seeds of a fully fledged multiparty system flourished once more. No one form of government predominated but single party governments were a regular feature until 1989.

PRSTV was designed into the politics of the Free State to provide representation for the minority Anglo Irish community and it did achieve that, at least for a time through the university seats and electoral rules. Joe Lee (1989: 83) notes with some irony that the first minority saved by PRSTV was Anti-Treaty Sinn Féin which would surely have been decimated in a system using FPTP. Minority voices were accommodated but it would be wrong to assess the Free State as a place where proportional representation delivered consensus politics and sensitivity to minority rights and needs. On balance PRSTV operating in a largely homogenous polity provided a majoritarian form of politics. The dominant group was able to impose its values and preferences on the whole. The Anglo Irish community did not organise effectively in politics; many left, some were absorbed into other political movements and their distinctive identity faded from political debate. Furthermore a reduction in the district magnitude in 1935 created a form of electoral threshold that kept fractionalization low (Gallagher, 2005: 517, see also Chubb 1992: 134). Levels of electoral integrity were moderate, malapportionment was largely absent due to constitutional constraints but bouts of gerrymandering were not unknown. Political context matters and the electoral system for a long time delivered broadly proportional outcomes reflecting the conservative, quite authoritarian if stable orientation of the vast majority of the electorate.

Electoral engineering employed a different system in Northern Ireland, one that also led to majoritarianism infusing elections, policy and politics but in a much more comprehensive and stifling way. Elections to the Northern Parliament (Stormont) were first held in 1921 using PRSTV. Conn O’Leary (1979: 9) points out that unionists won 40 of the 52 seats in the parliament while the divided nationalists picked up just 12 seats (23%), although they received just under one third of the votes. Disproportionality declined somewhat at the 1925 election and the Ulster Unionist Party (UUP) dropped to 62% of the seats on 55% of the votes. PRSTV was replaced with FPTP for local elections in 1923 and for parliamentary elections to Stormont in 1929. FPTP is a majoritarian system and it delivered extreme majoritarian outcomes in Northern Ireland. In the first election using FPTP, the UUP took 72% of the seats with 51% of the votes. It is widely argued that the decision to abolish PRSTV served partisan and class interests in the unionist community (Pringle, 1980; Coakley, 2009). There was a dominant two party system and single party government, features that were not interrupted until 1972 as Niall Ó Dochartaigh (2021) has argued. John Coakley

(2021) has also been to the fore in demonstrating that the adoption of FPTP ‘reinforced the bipolar character of the party system’.

In addition to the choice of electoral system, the wider abuse of electoral laws, gerrymandering and malapportionment meant that elections in Northern Ireland for many decades had low levels of electoral integrity. This point is made by Brendan O’Leary (2019: 114) who has argued that although Northern Ireland had ‘formal democratic rules’, the operation of those rules in practice leads to very ‘qualified assessments’ of the nature of early Northern Irish democracy.


In concluding, if I might return to the opening statement of Gallagher and Mitchell’s definitive book on the topic where they say ‘Electoral systems matter’. They do.

And it is also true to say that their impacts and logics are mediated through political culture, the underpinning cleavages that shape politics and electoral laws.

In Northern Ireland and the Free State, PRSTV and FPTP facilitated the dominant communities in imposing their will for many decades. Majoritarian spirit infused politics in both jurisdictions but one system had political legitimacy, the other did not. In Northern Ireland, a majoritarian electoral system was chosen specifically to limit minority representation and it was combined with notable abuse of the principles of electoral integrity.

In the Free State, the much smaller minority community achieved political representation and voice, initially disproportionately larger than their electoral weight. The 1937 constitution designed out some of the electoral advantages of the Anglo Irish community but lack of political organisation also contributed to the diminution of their representation over time. As the decades progressed, PR delivered election outcomes with much lower levels of disproportionality than that of FPTP in Northern Ireland. And importantly PRSTV is widely supported by the electorate. Blais and Masicotte (2002: 65) describe the system as giving ‘maximum freedom’ to voters. Despite two referendums and several serious reports later, there are no serious signs that voters in the Republic could be persuaded to relinquish the power bestowed by PRSTV. And of course Northern Ireland has reintroduced PRSTV.

Historians and political scientists have tended to focus on different aspects of the impact of PRSTV in the Free State-Republic of Ireland but there is widespread agreement that the electoral system choice was central to the enduring political stability that was achieved (Lee, 1989; Coakley, 1991) and equally in Northern Ireland there is general agreement that the majoritarian outcomes delivered by FPTP exacerbated embedded community division (Coakley, 2021).


Blais, A., 1991. The debate over electoral systems. International Political Science Review, 12(3), pp.239-260.

Blais, A. and Carty, R.K., 1991. The psychological impact of electoral laws: measuring Duverger's elusive factor. British Journal of Political Science, 21(1), pp.79-93.

Blais, A. and Masicotte, L., 2002. ‘Electoral Systems’ In LeDuc, M. L., Niemi, R. G., & Norris, P. (Eds.). Comparing democracies 2: new challenges in the study of elections and voting. Sage. Coakley, J., 2009. The political consequences of the electoral system in Northern Ireland.

Irish political studies, 24(3), pp.253-284.

Chubb, B., 2014. The government and politics of Ireland. Routledge. Gallagher, M., 2005. Ireland: the discreet charm of PR-STV. The politics of electoral systems, pp.511- 532.

Gallagher, M. and Mitchell, P. eds., 2005. The politics of electoral systems. OUP Oxford. Horowitz, D.L., 2003. Electoral systems: A primer for decision makers. Journal of Democracy, 14(4), pp.115-127.

Lee, J.J. and Lee, J.L., 1989. Ireland, 1912-1985: politics and society. Cambridge University Press.

Lijphart, A., 1994. Democracies: Forms, performance, and constitutional engineering. European Journal of Political Research, 25(1), pp.1-17.

Massicotte, L., Blais, A. and Yoshinaka, A., 2004. Establishing the rules of the game: Election laws in democracies. University of Toronto Press.

Moser, R.G. and Scheiner, E., 2012. Electoral systems and political context: How the effects of rules vary across new and established democracies. Cambridge University Press.

Norris, P., 1997. Choosing electoral systems: proportional, majoritarian and mixed systems. International political science review, 18(3), pp.297-312.

Dochartaigh, N.Ó., 2021. Beyond the dominant party system: the transformation of party politics in Northern Ireland. Irish Political Studies, 36(1), pp.7-28.

O'Leary, B., 2019. A treatise on Northern Ireland, volume I: Colonialism. Oxford University Press.

O'Leary, C., 1979. Irish elections, 1918-77: parties, voters, and proportional representation. Gill and Macmillan.

Pringle, D.G., 1980. Electoral systems and political manipulation: A case study of Northern Ireland in the 1920s. Economic and Social Review, 11(3), pp.187-205.

Singer, M.M., 2013. Was Duverger correct? Single-member district election outcomes in fifty-three countries. British Journal of Political Science, 43(1), pp.201-220.

Taagepera, R. and Qvortrup, M., 2012. Who Gets what, when, how–through which Electoral System?. European Political Science, 11(2), pp.244-258