Proportionality and exaggeration in the British electoral system

EIectoraiS&kr

(1986). .5:3, 209-228

Proportionality and Exaggeration British Electoral System

in the

JOHN CURTICE* Department of Political Theory and Institutions, U~~ue~s~ty of ~~er~oo~~ Lb9 3BX, Engtand MICHAEL STEXD

Department of Government, University of Manchester, Ml3 9PL, England

The British electoral system has traditionally been defended on the grounds that its systematic exaggeration of the lead of the Conservatives over Labour or vice versa secured for the largest party an overall majority of seats on a minority of the votes and thereby enabled the electorate directly to determine which party holds office. Recent changes in the electoral geography of Britain have eroded that systematic exaggeration at Westminster elections and may soon remove it entirely. Meanwhile the electoral system is discouraging the pursuit of geographically aggregative policies. Consequently, the single member plurality system is no longer a suitable’instrument to achieve the ends of its defenders but, despite their availability, alternative systems which could meet those aims have not been seriously considered.

Introduction The advent of the Liberal/SDP Alliance and its past and possible future electoral performance has put the issue of electoral reform firmly in the centre of British political debate. Despite only winning 2 per cent less of the vote than the Labour party at the 1983 general election it won 29 per cent less seats; the result was unusually ~spro~~ional even by the normal standards of the single member plurality system (McAllister and Rose, 1984: 24-5). Simulations of what might happen in future were the Alliance to become the second most or even the most popular party in terms of votes suggest that it could well remain firmly the third party in terms of seats. 1 The electoral system, it is claimed, has reached a threshold of unfairness which it is no longer possible to tolerate. This argument has one main drawback; it evaluates the single member plurality electoral system by different criteria than those used by its defenders.’ The system has been defended, not on the grounds that it produces a ‘fair’ result, but rather that it enables the electorate to choose between alternative governments and that it encourages governments to be responsive to the wishes of the electorate. 3 These quaiities are ascribed to the system

* Revised and expanded version of a part of a paper given at the Joint Sessions of Workshops of the European Consortium for Political Research, University of Salzburg, 1984. 0261-3794/86/03/0209)-20/503.00

0 1986 Butterworth & Co (Publishers) Ltd

110

Proportionality and Exaggeration in the British Electoral System

because it supposedly exaggerates leads in votes into larger leads in terms of seats, that is, systematic ‘unfairness’ can be a virtue. Four years ago we questioned how far the British electoral system still retained the qualities prized by its defenders (Curtice and Steed, 1982). We argued that significant changes in the country’s electoral geography had seriously undermined the exaggerative quality of the electoral system. But the re-election of Mrs Thatcher in 1983 with an overall majority of 144 on just 42 per cent of the total UK vote appeared to have undermined our argument. In this article we reconsider the validity of our thesis in the light of subsequent developments. We will demonstrate that apart from one important point-the exceptional size of the Conservative lead over Labour-the result of the 1983 general election proved to be a dramatic confirmation of our thesis. The exaggerative quality of the single member plurality electoral system is contingent upon the existence of certain circumstances which no longer pertain at Westminster elections. In consequence, even if the Alliance remains the third party in terms of votes the electoral system can no longer be defended on the grounds commonly used by its defenders. We also have two further aims. One is to explore the consequences of a continuation of the trends that have undermined the exaggerative quality of the electoral system-a growing divergence in electoral geography between North and South and between urban and rural areas. The second is to look at some of the wider implications of our findings for the debate about electoral reform. Although our original article has received considerable attention, many writers have focused upon what we had to say about the changing geography of Conservative and Labour support rather than that change’s consequences for an evaluation of the electoral system.’ Here we concentrate on evaluation rather than explanation. In particular we wish to suggest that the terms of the debate about electoral reform in Britain are too narrow and that defenders of the existing electoral system should be looking to alternative means of achieving their aims. In the next two sections we summarize why the single member plurality system was believed to be suitable for the ends of its proponents and how the changing political geography of Great Britain has undermined its exaggerative quality. These sections largely summarize and update our previous findings. We then proceed to examine how the electoral system might operate if recent trends were to continue in future. Although we discover that the exaggerative quality of the electoral system in its relative treatment of Conservative and Labour is close to disappearing entirely, the following section shows that important exaggerative features still exist. Finally in the conclusion we indicate what we consider the implications of our findings to be for the debate about electoral reform.

The Exaggerative

Quality

Central to the defence of the single member plurality electoral system has been its exaggerative quality. There are two elements to this. The first is relatively straightforward. It is argued that the system makes it difficult for small parties to win seats and thus representation in parliament tends to be dominated by two parties who compete with each other for office. It is now widely appreciated that this claim is only partly true. The single member plurality electoral system discriminates against small (and not so small) parties with a geographically evenly spread vote (such as the Liberal party) but not against those parties whose vote is geographically concentrated, such as the Northern Ireland Uni0nists.s But it is clear that the system does make it difficult for a small party with a nationwide basis of

JOHN CURTICEAND MICHAELSTEED

211

support (and thus perhaps a party with the potential to become a national party) to achieve effective representation. The second element in the claimed exaggerative quality of the single member plurality electoral system is a little more complex. The system not only helps larger parties at the expense of smaller ones, but also benefits the largest party at the expense of the second largest. The lead of the winning party over the second party in terms of seats is an exaggerated reflection of its lead in terms of votes. This exaggerative quality has been modelled in the form of a cube law. If the two largest parties share their joint vote between them in the ratio A:B, they will divide their seats in the ratio Aj:Bj. This means that a result close to a 50: 50 division of the vote, a 1 per cent transfer of votes would produce a 3 per cent switch of seats.6 Research suggested that the law applied not only in Britain, but also in the other Anglo-Saxon democracies using the same or a similar electoral system (Kendall and Stuart, 1950; Butler, 1951; Butler, 1963: 194-204; Qualter, 1968; Hughes, 1979). The law has thus become widely regarded as an integral feature of the single member plurality electoral system.’ With these two elements of exaggeration, the single member plurality electoral system was able to achieve the objectives of its advocates. The squeeze on (some) small parties together with the operation of the cube law meant that the largest party usually won a safe overall majority despite having less than 50 per cent of the vote. In consequence, the government was chosen directly by the people rather than determined by coalition bargaining. Further, the security of office given to governments helped to produce stable and effective government. While the exaggerative quality of the electoral system gives one party unfettered power for a period of-years, it also encourages its responsible use. Because the winning party’s overall majority is vulnerable to a small loss of votes it has to be responsive to a wide range of public opinion (Chandler, 1982). Under a Downsian logic (Downs, 1957), it is encouraged to stay in the ideological centre and thus much public policy will be operated under a Butskellitetype consensus. Equally, the vulnerability of a significant proportion of its seats to a small switch of votes means that the government will take cognizance of a wide range of geographical interests. In their seminal work which demonstrated the statistical underpinning of the cube law, however, Kendall and Stuart (1950) demonstrated quite clearly that the cube law would only operate if certain conditions were met. As in the case of its treatment of small parties, the single member plurality electoral system only exaggerated the distance between the two largest parties in conformity with the cube law if a certain geographical distribution of the vote existed. The distribution of the votes of the two main parties across the constituencies had (approximately) to represent a normal distribution with a standard deviation of 13.7. Although, a number of writers (including Kendall and Stuart themselves) have suggested reasons why these conditions should be fulfilled,* the operation of the cube law never has been inevitable. This is now evident in the case of Britain. The last thirty years have seen a persistent and dramatic change in its electoral geography which has all but removed this second element in the exaggerative quality of its electoral system.

The Decline

of the Cube Law

In order to understand the decline of the cube law in Great Britain we need to examine the constituency by constituency variation in the net movement between the Conservative and Labour parties (‘swing’) over the last 30 years. 9 At each of the last eight general elections, starting in 1959, the variation in swing since the previous election has reflected a socio-

Proportionality and Exaggeration in the British Electoral System

212

geographic pattern of two overlapping cleavages, North/South and urban/rural. At most elections one of the two has been the stronger. but at almost every election both have been present. The urban/rural cleavage was not clearly present until 1964, but thereafter at each of seven elections, Labour fared better in the cities and the Conservatives better in the countryside. The regional cleavage has varied somewhat across time. In 1959. and again in 1983. it could be described as a North-WestSouth-East cleavage. But over the longer term a simple North/South dimension, with Labour gaining ground in Scotland and the North of England, and the Conservatives gaining in the Midlands and South of England, is the best description of the pattern. There have been some short-term reversals to this pattern. In particular, South-East Lancashire moved to the Conservatives in 1970, as did Scotland in February 1974, while part of the West Midlands conurbation (the ‘Black Country’) swung unusually strongly to Labour in February 1974. But the only example of a long-term switch in the behaviour of a region during the last 25 years has been Wales which swung towards Labour until 1970 but to the Conservatives thereafter; Wales is therefore not covered in Table 1. All other regions have moved fairly consistently towards either Labour or the Conservatives since 195 5.

deviations in swing 1955-83

TABLE 1. Socio-geographical South of

England

i\Iidlands

North of England

Scotland

All

-8.5 -8.0 - 5.8 -4.8 - 1.1 - 0.4

- 3.9 - 2.8 -0.1 + 1.4 + 3.2 + 2.7

-4.8

(a) 1955-70 City Very urban

- 1.0 + 1.1

Mainly urban Mixed Mainly rural Very rural

+ 2.2 +4.0 +4.6 + 6.0

-6.5 -4.6 - 1.1 + 0.8 - 0.4 + 2.3

All

+ 2.2

- 2.0

0

(b) 1970 (NV-79 -7.2 -4.3

- 10.6

-4.5

-9.6 -6.7 - 2.7 - 2.2

-2.8

City Very urban Mainly urban Mixed Mainly rural Very rural

- 2.2 -1.0 + 1.8 + 3.8 + 5.4

- 3.1 +0.3 + 1.3

+6.3

+ 5.3

+ 1.5

All

+ 1.8

- 2.4

-5.3

-0.8 + 2.0 + 3.8 + 6.0 0

(c) 1979 (N-Q-83 City or very urban Mainly urban Mixed Mainly or very rural

-0.6 + 3.8 + 4.7 + 3.3

-4.1 +1.0 + 1.9 + 5.1

- 5.6 -3.1 -0.8 +o.o

- 8.4 -6.7 -3.9 +0.9

All

+ 2.4

+ 1.0

- 2.8

-3.7

- 2.9 - 0.4 +1.1 + 2.9 0

Each entry is the difference between the mean swing in the category and the mean swing in all constituencies. A plus sign (+) indicates a deviation in the Conservatives’ favour, and a minus sign ( -) a deviation in Labour’s favour. (NT = Notional results based on new boundaries)

JOI-N CUR-IKE&ND ~~ICH.~ELS~ED

213

Table 1 measures these movements in terms of the deviation from the national (mean) swing over three periods. The periods were determined by the incidence of boundary changes. We have had to construct a ‘bridge’ across the boundary changes by using both the actual election results in 1970 and 1979 and a recalculation of those results on the constituency boundaries used at the following election. t” Table 1 is derived from more detailed tables published for the 1955-79 and 197943 periods,” and the discrepancy in the regional and urban/rural categories between the two periods reflects the classifications which were most appropriate for each in turn. This inconsistency, as does some of the detailed variation within each part of the table, reflects the fact that the precise division between urban and rural, North and South, has varied somewhat over time. For example, inner suburban seats (particularly in Greater London) have sometimes acted like their city centre neighbours, and sometimes like outer suburbia or the rural hinterland. But the most striking feature of Table 1 is the consistency of movement during the three periods. The consequence of this consistency of variation is that cumulatively the variation has been massive. At one extreme, Scottish cities have experienced a total deviation of some 27.5 percentage points towards Labour, while rural constituencies in Southern and Mi~and England have moved altogether some 15 percentage points towards the Conservatives. This cumulative systematic variation in swing has fundamentally altered the exaggerative quality of Britain’s electoral system. The key to understanding how variation in swing can affect the exaggerative quality of an electoral system lies in its impact upon the distribution of the two-party vote. Any uniform swing will leave the distribution of the two-party vote unaffected. Equally, so will any nonuniform swing whose variation is randomly distributed among constituencies so that there is no correlation between swing and past performance. 12 But any swing which is correlated with past performance will affect the distribution of the two-party vote. If both parties do well in their weaker areas the standard deviation of the distribution of the two-party vote will fall and the exaggerative quality of the electoral system will increase: if both do well in their stronger areas the opposite will happen. A further point should be noted. Any long-term cumulative systematic variation in swing will eventually, if it continues long enough, result in an increase in the spread of the twoparty vote and a decline in the exaggerative quality of the electoral system. For even if a longterm variation in swing initially produced a negative correlation between past strength and swing, that swing would, by making one party’s weaker seats stronger for that party and ultimately safe (and vice versa), eventually result in a positive correlation between past performance and swing. These a priori considerations lead us to anticipate therefore that the long-term variation in swing seen in Great Britain since 1955 would eventually increase the spread of the twoparty vote. The variation may not initially have had much impact-it might even have resulted in an increase in the exaggerative quality of the electoral system-but we would expect that ultimately it would start to decline. The actual impact of the long-term variation in swing upon the exaggerative quality of the electoral system is shown in Table 2. This shows the standard deviation and kurtosis of the two-party vote in Great Britain at each election since 1955. It also shows the number of marginal seats both in terms of absolute numbers and as a proportion of all seats that are marginal. A marginal seat is defined as a seat which, at a 50:50 division of the overall twoparty vote, would be held by the winning party by a majority of 10 per cent of the two-party vote or less.‘3 For the cube law to operate, 30 per cent of seats should lie within this crucial area. Table 2 shows that there has been a dramatic change in the distribution of the two-party

214

Proportionality

and Exaggeration in the British Electoral System

TABLE 2. Changing

1955 1959 1964 1966 1970 1970 (NT) 1974 (Feb)

1974 (act) 1979 1979 (NT) 1983

distribution 1955-83

of two-party

Standard deviation

Kurtosis

13.47 13.79 14.12 13.77 14.34 14.32 16.10 16.82 16.86 16.56 20.02

-0.25 -0.29 - 0.45 -0.46 - 0.27 -0.30 - 0.68 -0.82 - 0.87 -0.91 - 1.05

vote

Marginal seats No. % 166 157 166 155 149 140 119 98 108 100 80

27.2 25.7 27.3 25.6 24.5 24.3 19.9 16.4 17.8 16.1 13.2

vote. In 1955 Britain did largely conform to the cube law, though a somewhat flatter than anticipated distribution meant that there were slightly less marginal seats than would have been expected. By 1983 the standard deviation of the two-party vote had increased considerably, the kurtosis fallen, and the number of marginal seats been more than halved. Until 1970 the fall was slight, which as we have shown elsewhere was principally because the correlation between past performance and swing was not strongly positive, (Curtice and Steed, 1982: 274-80) but thereafter there has been a sharp fall in the number of marginal seats. More and more Labour seats became more Labour, and more and more Conservative seats more Conservative.t4 The limited ability of the British electoral system operating with the 1983 distribution of the vote to exaggerate the lead of the largest party over the second party is illustrated in Table 3. It shows what the distribution of seats between Conservative and Labour would be if the allocation of seats were strictly proportional, and if it were according to a square or cube law. This is contrasted with the actual distribution of seats that would occur as a consequence of a uniform shift from the 1983 result, assuming that no seats were won by third parties. It is clear that for any result likely to occur so long as Conservative and Labour remain the principal competitors for power that the exaggerative power of the British electoral system is now very mild, being less not only than that of the cube law but also less than that of a square law. This decline in the exaggerative power of the electoral system acquires additional significance because of the modest increase in the number of third-party hIPs in the House of Commons. This has been brought about not only by the increase in the number of Liberal/Alliance and Nationalist MPs from Great Britain but also by the divorce of Northern Ireland politics from that on the mainland and an increase (in 1983) in the province’s total representation from 12 to 17. At the 1959 election third party representation reached an all-time low of 7 MPs. But the February 1974 election marked a significant break in the Conservative and Labour parties’ virtually total domination of the House of Commons when 33 third-party MPs were elected. Their numbers have since never fallen below 27 and in 1983 reached 44. The decline of the ability of the electoral system to exaggerate the lead of the largest party over the second has occurred at a time when it was increasingly needed if elections were to continue to produce safe overall margins for one party. An indication of the prospects for a hung parliament in the continued absence of a parliamentary breakthrough by the Alliance is given in Table 4. The table assumes that the

JOHNCURTICEAND MICHAELSTEED

215

TABLE3. Exaggerative quality of electoral system Actual 1983

Distribution of the 633 seats proportional squared cubed

Voting ratio 50:50 52.5:47.5 55:45 57.5:42.5 60:40 60.6:39.4

316:316 332:301 348:285 364:269 380:253 384:249

316:316 348:285 379:254 409:224 438:195 445:188

316:316 364:269 409:224 451:182 488:145 497:136

Con:Lab

Lab:Con

326:307 345:288 365:268 387:246 414:219 417:216

307:326 326:307 353:280 371:262 400:233 -

Source: Curtice and Steed (1984) TABLE 4. The current seats/votes relationship % Vote (GB) Con. Lab.

Con.

Lab.

43.5 42.5 41.5 40.5 39.5 38.5 38.0 37.5 36.5 35.5 34.5 33.5 32.7 32.5 31.5

397 387 370 355 340 332 326 318 ‘305 297 286 273 265 259 244

209 217 233 246 259 266 271 277 290 300 310 318 326 331 345

28.3 29.3 30.3 31.3 32.3 33.3 33.8 34.3 35.3 36.3 37.3 38.3 39.1 39.3 40.3

Seats (UK) All. 0th. 23 25 26 27 28 28 :: 31 29 29 34 34 36 37

21 21 21 22 23 24 24 24 24 24 25 25 25 24 24

Maj. Con. Con. Con. Con. Con. Con. Con. None None None None None Lab. Lab. Lab.

144 124 90 60 30 14 2

2 12 40

Alliance wins the same share of the vote in Britain (26 per cent) and in each constituency as it did in 1983 and then explores the impact of successive transfer of 1 per cent of the total British vote from Conservative to Labour. We find that the Conservatives need to retain at least a 4.2 per cent lead over Labour if they are to have an overall majority, while Labour need to acquire a lead of at least 6.4 per cent. The difference between the two figures reflects the impact of electoral bias which will not necessarily have the same impact at the next electionIs We can thus best summarize the results of Table 4 by concluding that the Conservatives and Labour need at least a 5 per cent lead over their principal opponents to have a reasonable chance of an overall majority. Such a lead (in Great Britain) has not been common in post-war elections. Only on three occasions, since 1950-in 1966, 1979 and 1983-has it been achieved. The 1983 lead of 15 per cent in particular was wholly exceptional, being more than twice that achieved by either party in any other election since 1950. It was a lead of that size which we had not anticipated in our original article (Curtice and Steed, 1982: 295) and which means that the decline in the exaggerative quality of the electoral system has failed to register its effects more clearly in the House of Commons. But should British elections return to the post-war norm of close competition between Conservative and Labour, the electoral system will demonstrate a profound inability to produce single-party government with safe overall

216

Proportion&y

and Exaggeration in the British Electoral System

majorities. Even a return to lower levels of third-party voting on the British mainland would do little to restore the electoral system’s ability to produce overall majorities. If the Alliance vote were to decline to 20 per cent (around the lowest it has been in opinion polls since 1983). the Conservatives would still need a voting lead of 2.8 per cent and Labour, 4.8 per cent. The claim that ‘on present trends the likeliest outcome of the next election is a hung parliament, all recent opinion poll evidence points this way. And the main reason is the rise and permanence of the LiberaliSDP Alliance and the /act that they ‘r-e now quite Me/y to have a significant number of members of Parliament’ (Kellner, 1985: our emphasis) completely misidentifies the main reason why hung parliaments are now likely.

The Future The foregoing analysis assumes that the decline in the number of marginal seats is unlikely to be reversed in the near future. Clearly we cannot be certain of what will happen, but it seems extremely unlikely. Indeed, it seems to us more likely that the North/South urban/rural variation in swing will continue and it is therefore useful to consider what the consequences would be if that were to happen. One of the principal difficulties in predicting future trends in Britain’s electoral geography is that very little research has been conducted into the reasons for the changes that have occurred so far or, indeed, into the factors behind the spatial division of the vote in Britain at all (Johnston, 1984). We ourselves put forward three possible explanations in 1982 as to why the North/South urban/rural variation might have occurred and could be expected to continue-change in the geographical distribution of social classes due to the pattern of migration (particularly from the cities to rural areas), an increase in the importance of the class composition of the neighbourhood as an influence upon voting behaviour, and the development of a territorial cleavage (Curtice and Steed, 1982: 261-4).16 As we have seen, the 1983 general election did indeed see a further continuation of the variation suggesting that our general conclusions at least were correct. Indeed, it is probably true that ultimately many of the factors which have brought about the change in the electoral geography .of Britain were themselves caused or encouraged by changes in the country’s economic geography. The population decline of the cities and the relative decline in the population of Northern Britain, for example, reflects their relative economic weakness. There seems to be no reason to expect a change in these economic forces in the near future (Dicken, 1982; Massey. 1984). Thus recent analysis of the differences in the standard of living between the regions has revealed a widening of the gap between the South (and in particular the South-East) and most other parts of Great Britain (Central Statistical Office, 1986). Meanwhile, analysis of the spatial distribution of population growth and migration since 198 1 has shown that although the rate of change has fallen, the trends of the 1960s and 1970s are continuing (Britton, 1986). What then could be the implications for the future exaggerative quality of Britain’s electoral system of a further continuation of the past pattern of swing? We can answer that question by undertaking a very simple exercise. We can take the 1983 geographical distribution of the vote and see what would happen to the number of marginal seats if the variation in swing of the recent past were to be repeated in the near future. As our measure of the recent variation in swing we have calculated for each constituency the extent to which its swing deviated from the national average between 1970 and 1983.” The effect of a repetition of this variation is then explored by adding one-half, the whole, and one and a halftimes this deviation to the 1983 general election result in each constituency in order to estimate the distribution of the two-party vote at three hypothesized future elections. The

JOHNCURTICEASD MICHAEL STEED

217

number of marginal seats (using the same definition as before) that would result is shown in Table 5 below. Further continuation of the past pattern of swing would clearly result in a further fall in the number of marginal seats and a decline in the exaggerative quality of the electoral system. Indeed, that exaggerative quality is close to disappearing completely. If there are 60 marginal seats in a 600 seat legislature then each 1 per cent swing results in exactly 1 per cent of the seats changing hands: the electoral system is proportional in its relative treatment of the two largest parties. As can be seen, a further one-half of the deviation in swing that occurred between 1970 and 1983 would produce just that situation. Any further deviation, and the British electoral system would become less responsive to swings of electoral opinion between Conservative and Labour than a proportional system would be. Theoretically, if the variation were to continue indefinitely all existing marginals would eventually become safe seats for one party or the other. However, as can be seen from Table 5, the rate of decline in the number of marginal seats is reduced once the number falls below 60. Although the source of new marginals (the seats held safely by one party in a type of area moving systematically against it) will by then be nearly exhausted, many of those that are marginal show little tendency to become safe. There are indeed about 20-30 seats (4 per cent of all seats) which are likely to remain marginal in the foreseeable future even if there is a strong continuation of the North/South urban/rural variation in swing.r8 They are amongst the few constituencies which have recently swung in line with the national average. Some of them are scattered around the country. but the majority occur in one of the three situations where, as Table 1 shows, the regional and urban/rural influences appear to be in balance, leaving their marginal quality undisturbed: 1. Mixed’9 constituencies in North-West England, along the outer fringe of the Greater Manchester and Merseyside (for example, Pendle, Chorley). 2. Constituencies in the transitional zone between the inner and outer zones of Greater London (for example, Ealing North, Mitcham & iLlorden). 3. Constituencies in medium size cities (100,000 to 400,000 population) in the southern half of Britain (for example, Nottingham South, Southampton Test). On present trends, therefore, it seems unlikely that we will reach the extreme situation where the electoral system will completely fail to register shifts of support between Conservative and Labour. But the minimum likely number of marginal seats would leave it no more than half as responsive as a proportional system would be. So far we have considered the likely future trend in the number of marginal seats but not the speed at which the apparently inevitable change will occur. This must remain very much a matter for speculation particularly in view of the uncertainty as to the exact causes of the variation in swing. What is clear is that the speed of the divergence in political geography has been increasing. Inspection of Table 1 reveals that each of the three periods of 16. 9 and 4 years in length has seen approximately the same amount of divergence. Thus the rate of TABLE 5.

Marginal seats in future

Marginal seats Effect of one-half deviation % No. IMarg. seats lost Marg. seats gained 1983 Election A Election B Election C

13.2 9.6 8.7 7.1

80 58 53 43

- 28 - 14 -13

+6 +9 +3

Proportion&y

218

and Elvaggerotim in the British Eiectorul System

divergence per annum was by 1979-83 nearly four times as fast as in 1955-70. At the present speed of divergence, we are heading quickly for the situation where the eiectoral system will have lost its exaggerative quality. On that basis the equivalent of onehaff of the total 1970-83 divergence will have occurred by the time of the next election. In other words. on a litera projection of the 1979-S3 speed our three hypothetical elections A, B and C in Table 5 indicate the degree of exaggeration to be expected of the electoral system at the next three general elections should they follow parliaments of a normal length. If so, then we can anticipate: -that after the next general election (due in 1987 or 1988) the number of Conservative and Labour marginals will have fallen to around 60 (10 per cent of the total). The electoral system will no longer exaggerate the lead of the Conservatives over Labour or vice versa but be proportional between them. -that by early in the next century, the number of two-party marginals will stabilize at around or slightly below 30 (5 per cent of the total). The electoral system will dampen the lead of the Conservatives over Labour or vice versa. It wilt only be half as responsive to a swing between them as a pro~rtional system would be.‘”

The Exaggeration

That

Remains

We have demonstrated so far that the single member plurality electoral system has now almost lost its ability to exaggerate the relative electoral strength of the Conservative and Labour parties in terms of the seats that they win. But while the relative sizes of the Conservative and Labour parliamentary parties are little different from what would be produced under a system of proportional representation their composition is very different. For while the electoral system fails to exaggerate the lead of one party over the other at national level, it still produces substantial exaggeration of the lead of one party over another in any particular region. This point is demonstrated in Table 6. The regions in the Table have been defined in such a way as to distinguish those parts of the country which are predominantly Conservative and T.+BLE6. Parliamentary 1951

Seats

geography

1974 (Feb) Seats Con. Lab.

1983 adjusted to 50:50 voting ratio Seats Votes % Con. Lab. Con. Lab.

Con.

Lab.

South and East shire counties Outer London Midland shire counties

118 36 26

24 18 35

135 35 35

21 19 27

151 36 41

17 14 27

66.2 55.9 53.4

33.8 44.1 46.6

Conservative

180

77

205

67

228

58

61.4

38.6

14

33

7 7 8 49 21

31 25 24 114 40

3 8 8 41 11

27 23 25 115 49

35.9 42.2 34.7 40.5 34.1

64.1 57.8 65.4 59.5 65.9

92 234

71

239

38.6

61.4

299

297

50.0

50.0

Britain

Inner London West Midland met. county Wales North of England Scotland

7 22 6 27 70 101 35 35

Labour Britain

132

218

House of Commons

312

295

Source: Curtice and Steed, 1984.

297

301

JOHS CURTICEANDMICHAELSTEED

219

those which are predominantly Labour. Table 6 shows the distribution of seats between Conservative and Labour within each region in 195 1 and February 1974 (when the two parties almost tied with each other in terms of votes) and what the distribution would have looked like in 1983 assuming the existing electoral geography but overall national equality of votes. The final two columns show what the distribution of the two-party vote would have been in 1983 on the same assumptions. The exaggerative quality of the electoral system at sub-national level is immediately apparent. In the South and East shire counties, for example, the Conservatives would, in an evenly contested election, win two-thirds of the two-party votes, but 90 per cent of the seats. Across the whole of Conservative Britain the Conservatives would win just over three-fifths of the vote, but nearly four-fifths of the seats, while the result in Labour Britain would be almost a perfect mirror image. The distribution of seats in the two halves of the country separately is indeed close to the predictions of the cube law! The use of the single member plurality electoral system therefore results in a substantial amplification of the geographical variation in the electoral strength of the Conservative and Labour parties. Both parliamentary parties are dominated by representatives from areas of their electoral strength and, as can be seen, to a far greater extent than was true in 195 1, or even in February 1974. 21 Whereas in 1951 less than three-fifths of the Conservative parliamentary party came from ‘Conservative Britain’, the same result in 1983 would have seen over three-quarters do ~0.~~ The sometime exaggerative quality of the electoral system at the national level supposedly encouraged political parties to aggregate a wide range of interests and thus to operate not far from the consensus of the political centre. In so far as it has any consequences for the policy stances adopted by the political parties now it appears to encourage dissensus.23 The electoral system that fails to exaggeratgsubstantially the overall national division of the vote between the Conservative and Labour parties at the same time ensures that both parliamentary parties are dominated to a far greater extent than they would be under most forms of proportional representation by respresentatives from one half of Britain.2” A further implication of this analysis should also be emphasized. While we have demonstrated that the single member plurality system has virtually lost its exaggerative power at Westminster elections, this does not mean that it is not capable of producing an exaggerative result in Britain given the current political geography. In other contexts it may do so. Quite clearly we can anticipate from Table 5 that if it were to be used with Westminster sized constituencies in any regional assembly it is likely to exaggerate the ConservativelLabour lead. In the one such assembly that does currently exist-the Inner London Education Authority covering the whole of Inner London-the result of the 1986 elections conformed quite closely to the cube law.2r Equally, if Westminster sized constituencies were used in electing a Scottish or Welsh assembly (as was proposed for the assemblies which were rejected in the 1979 referendums) an exaggerative quality could be anticipated. Not only is the loss of the exaggerative power of the electoral system contingent upon its use throughout Great Britain, but equally upon the use of Westminster sized constituencies.26 Generally speaking, the larger the size of the constituencies the greater the exaggerative quality of the electoral system. This is illustrated in Table 7 in which we have estimated the proportion of marginal seats that would exist if Great Britain were divided into fewer constituencies.27 The cube law could still operate in Britain if it were divided into only 20 constituencies, while the division into the 78 existing European parliamentary constituencies produces sufficient marginal seats for the electoral system to have an exaggerative power slightly greater than a square law.2s

220

Proportzonality

and Exaggeration rn the British Electoral S_vstem

TABLE 7. The effect of constituency Number of British constituencies

size v/o

hlarginal seats 13.3 15.6 18.8 23.4 ‘S.2 30.0

623 312 156 78 39 20

Equally, our conclusion is not generalizable to the single member plurality system’s impact on the relationship between seats and votes in British local elections. No systematic research has ever been conducted into the subject and it is a too large one for us to tackle here. It is clear, however, that no simple statement can be made, for the degree of exaggeration is known to vary considerably from one local authority to another. The exaggerative quality of the single member plurality system is therefore governed by two main features-the spatial distribution of each party’s supporters and the size of the constituencies being used. The virtual loss of the exaggerative quality of the system at Westminster elections does not necessarily mean that, even on the existing spatial distribution of the vote, that quality cannot exist at other elections in Britain which use the same system.29

Conclusion The claim that the exaggerative quality of the single member plurality electoral system ensured that the electorate could directly choose between alternative governments has been fundamental to the argument in its favour. That exaggerative quality is, however. contingent upon circumstances. In Britain the last thirty years has demonstrated that fact quite clearly. Some parties have been able to secure parliamentary representation on relatively small shares of the overall vote because of the geographical concentration of their support. More importantly, its tendency to exaggerate the lead of the Conservatives over Labour or vice versa at Westminster elections has all but disappeared. Only if very much larger electoral units were to be used, such as in the European elections, can the electoral system now be expected to exaggerate the ConservativeiLabour lead significantly. The continued use of the single-member plurality system now seems likely to produce hung parliaments even in the absence of an Alliance breakthrough. The traditional defence of that electoral system has been rendered unconvincing. Indeed, in a number of significant respects, the British electoral system now exhibits qualities commonly anticipated in a proportional system. Firstly. underlying the highly exaggerative 1983 general election result are two important proportional features. The system was almost proportional in its relative treatment of the Conservative and Labour parties while it was reasonably close to providing absolute proportionality for those small parties whose vote is geographically concentrated. 30 It discriminated onlv against those parties whose vote is geographically evenly spread-principally the LiberaliSDP Alliance and the Scottish National Party (whose support is relatively evenly spread across Scotland). The proportionality of treatment which the British electoral system affords to most political parties can be quite easily demonstrated. In Table 8 we show both the actual 1983 general election result in terms of votes and seats and what the result looks like if we exclude

JOHN CURTICE.WD MICHAEL STEED

221

the votes cast for and the seats won by the Scottish National Party and the Alliance. On this basis the general election result looks fairly close to proportional. Indeed it scores 93.7 on the Rose Index of Proportionality, which is as proportional a result as those systems commonly called proportional achieve on average and more proportional than that produced by most of those which do not have some allocation of seats at national level (Rose, 1983: 41). A further decline in the number of marginal seats would, of course, erode most of the disproportionality that remains. Despite the changing electoral geography, one feature of the British electoral system has remained unchanged. It is still possible to argue as Pulzer did in his well known commentary upon elections and representation in Britain that, ‘. . . the relationship between votes and seats is almost as predictable in Britain as in countries with proportional representation’ (Pulzer, 1972: 56). But the regularity of the relationship does not consist of a systematically exaggerative relationship between votes cast and seats won. Rather, the electoral system discriminates sharpy between two different types of political parties. Amongst those parties whose support has a significant degree of geographical concentration it operates close to proportionality.3r But those parties whose support is geographically evenly spread are discriminated against until they reach a high threshold when it starts to operate in their favour.s2 That threshold is so high that even when they are second in votes (as were the SNP in Scotland in October 1974) or even first, 33 they can still be a poor third in terms of seats. Advocates of the existing electoral system have, therefore, not only to abandon any claim that the electoral system is systematically exaggerative along the lines of the cube law, but also have to be prepared to defend this differential treatment of political parties according to the nature of their support rather than according to their size. The second way in which the British electoral system now has the qualities commonly ascribed to proportional representation is in its potential to give disproportional power in the process of coalition formation to small parties. It is argued that small parties acquire that power in proportional systems because despite their size they can play a pivotal role in determining who holds office. 3’ If proportional representation were to be introduced into Britain now it is true. that on any likely result, the Alliance would play such a pivotal role-but it cannot be regarded as a small party. Under the continued use of the single member plurality system, however, it is quite possible that the truly small Northern Ireland Unionist parties would be able to play a decisive role in determining who holds office. As we have seen in Table 4, the electoral system is likely to deny both the Consenatives and Labour an overall majority, but they are also likely not to be far short of one. In that situation a dozen or so Unionist MPs elected on less than 2 per cent of the national vote could be in as TABLE 8. Proportionality

and exaggeration

1983 general election result Including all parties Excluding AllianceSNP Votes Seats Seats Votes Seats

% Conservative Labour Alliance Unionist parties SNP Republican parties Plaid Cymru Others

42.4 27.6 25.4 1.4 1.1 0.8 0.4 0.9

% 397 209 23 15 2 2 2 0

%

61.1 32.2 3.5

5:7 37.5 -

63.5 33.5

2.3 0.3

1.9 -

2.4

0.3 0.3 0.0

1.1 0.6 1.2

0.3 0.3 0.0

222

Proportionality and Exaggeration in the British Electoral System

powerful a position as an Alliance parliamentary group elected on 20 per cent. Thirdly, the decline in the number of marginal seats is eroding the claim that the single member plurality system is more responsive to shifts of popular support than proportional representation. It is already little more able than a proportional system would be to translate shifts of votes between Conservative and Labour into shifts of seats and on present trends will soon be less able to do so. If the Alliance fails to make a breakthrough. the electoral system will also continue to be unresponsive to shifts in its support. For example a 4 per cent increase in Alliance votes from its 1983 position taken evenly from Consemative and Labour would result in a shift of only 2% per cent of the seats; an equivalent 4 per cent fall only produces a loss of 1 per cent of the seats. This conclusion is given added weight by the exaggerative impact that the electoral system is still having upon the character of the Conservative and Labour parties. As we have demonstrated, the electoral system now has a more significant impact than it did thirty years ago in creating a regional imbalance in the composition of the Conservative and Labour parliamentary parties. Both this regional imbalance and the general unresponsiveness of the electoral system to swings of electoral fortune now actually discourages rather than encourages the development of aggregative policies designed to appeal to a wide range of groups. The properties that were assigned to the electoral system in the 1950s were contingent upon certain circumstances; so equally is our evaluation of it in the 1980s. It depends in part upon at least the maintenance of the existing geographical distribution of each party’s vote: we have given reasons why it seems reasonable to anticipate that the recent change in the geography of the Conservative and Labour vote will not be reversed. But it also depends upon a given distribution of political strength. We have evaluated the electoral system on the assumption that the Conservative and Labour parties will generally be in as close electoral competition as they have been for most of the post-war period. Meanwhile. although we assume the continuation of the divorce of Northern Ireland politics from that of the mainland, we have assumed that the Alliance’s support will fall short of the level required to achieve a substantial breakthrough. These assumptions have a clear heuristic value. They enable us to show that the maintenance of what is widely regarded as the post-war norm in the electoral politics of the British mainland will no longer produce the post-war norm of single-party majorit) governments. The assumptions also appear to us to be empirically reasonable. For example. the average lead of the Conservatives over Labour or of Labour over the Conservatives in opinion polls conducted since the 1983 general election until the time of writing has been just under 5 per cent; only in 10 of the 3 5 months in question was the lead larger than 5 per cent. Those same opinion polls have also regularly put the Alliance in third place and in only one month did their average opinion poll performance exceed 31 per cent.j5 But even a departure from these assumptions would not necessarily restore rhe case for the existing electoral system. Some commentators have suggested that the 1979 and 1983 elections herald a long-term Conservative superiority over Labour. Such an outcome would destroy any semblance of two-party competitive politics. j6 The electorate would no longer be choosing between alternative governments. Alternatively the Alliance might actually achieve a more substantial breakthrough into first place in terms of votes. But as we have already argued, the manner in which the electoral system treats its votes leaves no guarantee that in that situation the Alliance would be the largest party in terms of seats. let alone secure an overall majority. Continued support for the use of the single member plurality system in Britain is therefore no longer compatible with the pursuit of the aims traditionally promulgated by its advocates.

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223

Yet in the popular debate about electoral reform in Britain no alternative systems which achieve those ends have been proposed despite their undoubted availability. The debate has centred wholly upon the desirability of introducing some form of proportional representation or not. Central to the achievement of the traditional aims of the supporters of a plurality voting system has been a systematic exaggeration of the relationship between votes and seats irrespective of the nature of a party’s support. There are a number of instances when rules have been introduced by a country to achieve such a relationship. Greece has had considerable experience of a system of ‘reinforced’ proportional representation which between 1974 and 198 1 systematically discriminated against parties with less than 17 per cent of the vote. Thus, for example, New Democracy won 57.8 per cent of the seats in 1977 on 41.9 per cent of the vote. The Panhellenic Socialist Movement saw its secular increase in support quite systematically exaggerated by the electoral system. Thus in 1974 its 13.6 per cent of the vote brought it only 4.0 per cent of the seats; in 1977, 25.3 per cent of the vote secured a small bonus-30.2 per cent of the seats-while in 1981 slightly less than half of the vote, 48.1 per cent, achieved 57.4 per cent of the seats (Clogg, 1983). In 1985 further refinement of the system increased the systematic nature of the exaggeration it produced. Both Italy and France have also implemented rules permitting systematic disproportionality. Thus in 1925 the Italian electoral system guaranteed 60 per cent of the seats to the largest party so long as it won a quarter of the vote and in 1953 it did so to a party or alliance of parties that secured a half of the vote (Lakeman, 1970: 213-16; Nohlen, 1978; Carstairs, 1980: 156, 159). In 195 1 and 1956 the French electoral law gave all the seats in a multi-member constituency to any party or alliance of parties which won over 50 per cent of the vote (Lakeman, 1970: 222-4; Carstairs. 1980: 180-2). Further, although never actually implemented, proposals have been made in both the Netherlands and West Germany that a square or a cube law should be used explicitly to allocate seats.3’ All of these measures assume the existence of a political system in which the executive is responsible to the legislature. In any such system there is an inevitable conflict between the purpose of elections advocated by supporters of plurality systems-the election of a government-and the purpose emphasized by proponents of proportional representationthe election of a representative assembly. That conflict can, however, be resolved such that both purposes can be achieved. The most direct way of achieving the direct determination of the government by the electorate is to hold an election specifically for that purpose. This is achieved, for example, in presidential elections in the United States (in practice despite the existence of the electoral college), the Philippines and Fifth Republican France (in practice if not in theory at least until 1986). Where the electorate does directly elect the executive and that executive is not accountable to or too heavily constrained in its possible actions by the legislature, then the arguments in favour of any exaggeration of the relationship between seats and votes in the legislature largely fall (Duverger 1984, Johnston 1984). Thus proportional representation may also be introduced to achieve the aims of its advocates. Our purpose here is not to advocate any of these measures but rather to demonstrate the narrowness of the terms of the debate about electoral reform in Britain. There is a wide range of alternative measures which could achieve the traditional aims of the defenders of the single member plurality system more effectively than that system can now do. None of these alternatives has been given any serious consideration at all. Equally the debate has taken for granted the existing relationship between the executive and the legislature and yet consideration of the desirable relationship is fundamental to any evaluation of possible changes to the electoral system. The narrowness and defensiveness of the position adopted by advocates of the existing system was most strongly demonstrated by the insistence on

hportionaiit_v

224

und Elrugferation in the British ELectoral System

using the single member plurality system for the election of the British members of the European Parliament despite that body’s largely advisory and deliberative role. That position

might

yet be their undoing.

Notes 1. For example,

2.

3.

4.

5.

6 7. 8.

9.

10.

11. 12.

13.

14. 15.

16.

were the overall vote in Great Britain to be divided Conservative 33 per cent, Labour 30 per cent, Alliance 34 per cent as a consequence of a uniform shift of votes in each constituency, the Conservatives would win 229 seats, Labour 286 and the Alliance 110. The 1983 result was also unusually disproportional for any country using a plurality voting system. The index of proportionality (77) is lower than in any other country for which a figure is given in Table 8 of Rose (1983). As Nohlen notes, ‘Electoral systems should be classified and judged in accordance with the principle of representation that they are supposed to follow. They should not be judged on whether they fulfill any other principle of representation.’ (Nohlen. 1984: 88). See, for example, Chandler (1982). Taylor (1984). For further discussion of the differing principles underlying majoritarian and proportional systems see Curtice and Steed, 1982, pp. 249-52: Nohlen (1984). See, for example, Kavanagh. 1985, pp. 97-100; Johnston (1986). Some textbooks still ignore our findings completely. Richard Rose. for example, writes in the latest edition of his textbook, ‘It is normal for the electoral system to manufacture a majority in Parliament for a party with a minority of votes.’ (Rose. 1985: 276). In 1983, the Official Unionist party won 0.8 per cent of the overall UK vote. but 1.6 per cent of the seats. For further details on this point see Gudgin and Taylor, 1979, pp. 74-5 and 116-19; Curtice and Steed, 1982. pp. 287-91. For further details of the properties of the law see Gudgin and Taylor, 1979. pp. 26-30. But for a contrary view see Tufte (1973). Probaby the most convincing sociological account of why the cube law should occur in a polity where class is the principal electoral cleavage and a form of non-partisan districting is used has been supplied by Gudgin and Taylor. 1979, chap. 3. See also Kendall and Stuart (1950). March (1957), Taagepera (1972). Sankoff and Mellos (1972). Taagepera (1973). Throughout this article two-party swing is used. This is defined in the change in the Conservative share of the combined vote for Conservative and Labour. For further details see Steed (1965) pp. 337-8. The statistic therefore measures directly movement along the horizontal axis of the distribution of the two-party vote. The notional results used for 1970 (NT) were calculated by Michael Steed. The notional results for 1979 (NT) are a slighly revised version of the estimates calculated by a team of academics organized by the BBC and ITN (BBCITN 1983). The principles underlying our revisions are to be found in Curtice and Steed, 1984, pp. 368-9. See Curtice and Steed, 1982. Table 1; Curtice and Steed, 1984, Table 3, where details of the construction of the categories are also given. Strictly speaking there needs to be a slight negative correlation for the distribution to be unaffected. See Gudgin and Taylor. 1979, pp. 62-4. Traditionally it has indeed been claimed that swing was largely uniform and the limited variation randomly distributed. The 50:50 division is achieved by applying the necessary uniform two-party swing to the actual result in each constituency at each election. Until 1983 neither the Conservatives nor Labour succeeded in winning over 55 per cent of the two-party vote, and thus this definition encompasses all those seats likely to change hands as a consequence of a uniform national swing. Comparison of the figures for 1970 (NT) and 1970, and for 1979 (NT) and 1979. indicates that the two boundary revisions in this period had no significant effect. For further details on the bias in the electoral system see Curtice and Steed. 1984. pp. 361-2. The concentration of Labour’s vote in areas of population decline means that Labour increasingly benefits over time (until a boundary revision occurs) from a concentration of its vote in smaller sized constituencies. Any reduction in the bias against Labour at the next election would reduce the lead required by Labour, but increase that required by the Conservatives. Some subsequent support for the second and third of these has been given by the discovery by the 1983 election study of the importance of neighbourhood in influencing voting behaviour at that

JOHN CURTICEAND MICH.AELSTEED

17.

18.

19. 20. 21.

22.

23.

24.

25. 26. 27.

28.

225

election (Heath et al. 1985: chap. 6) and by McAllister and Rose’s analysis of the geography of the vote using aggregate data which did discover some territorial variation in electoral support which could not be accounted for by socioeconomic variables (McAllister and Rose, 1984). We also noted that the pattern of increase in the third-party vote had also accounted for some of the variations in swing. But that pattern did not affect the variation in swing in marginal seats and therefore had only marginal consequences for the exaggerative quality of the electoral system (Curtice and Steed, 1982: 264-6 and 275). The calculation was undertaken as follows. For each 1974-79 constituency the extent of its deviation from the 1970 (NT)-79 swing was calculated. Each 1983 constituency was then assigned a 1970 (NT)-79 deviation by calculating the weighted mean of the deviation of its using the figures given in BBCiITN (1983). This component 1974-79 constituencies, procedure effectively assumes that deviation from the national swing was uniform throughout divided 1974-79 constituencies. Since deviations were, for the most part, a reflection of the location of the whole constituency, this is on the whole a reasonable assumption and the few cases where it is not should not seriously invalidate our overall calculation. The total 1970 (NT)-83 deviation was then calculated by adding the estimated 1970 (NT)-79 deviation to the 1979 (NT)-83 deviation for each constituency. The 1970 (NT)-83 deviation for each constituency will, of course, not only reflect the influence of the long-term pattern of swing but also any short-term division (such as the effect of an MPs personal vote, party splits etc.) in the voting pattern present in 1970 or 1983 an&or any errors in the notional results for 1970 or 1979. Our procedure assumes these effects will cancel out. The averages given in Table 1 could not be used because boundary changes make it difficult to relate long-term averages to individual seats. Our procedure may underestimate the basic number of indefinite marginals since for each constituency it projects forward the effects of any local. short-term divergence in 1970 or 1983 (see note 17) as well as any long-term divergence. Inspection of the details of our results suggests, however, that this has at most only a slight effect upon our estimate. Most of these ‘mixed’ constituencies are relatively urban. often being based on an urban core or a straggling urban development. along with some rural fringe. This would not be unprecedented. It is exactly the experience of Northern Ireland in elections to the Stormont parliament between 1928 and 1969. Some detailed examples demonstrate the point quite clearly. When the Conservatives won the 1955 election they held 14 out of the 25 seats in the cities of Glasgow and Liverpool; after the 1983 elections, despite the Conservatives’ overall majority being three times greater, there were no Conservative MPs in either city. II-I1950, when Labour won an overall majority of just eight, there were 17 Labour MPs for county divisions in the South and East of England: in October 1974, when Labour won an overall majority of three. it held only three of those 17 seats. The change, in part of course, reflects the increase in the number of parliamentary constituencies in Conservative Britain. But note that, despite this, Labour’s absolute strength in that half of the country has declined. It is interesting to note in this context that the distribution of public expenditure shifted somewhat from Southern Britain to Northern Britain between 1969!70- 1973174 (when the Conservatives were in office) and 1974/75-1977/78 (when Labour were in office). See Short (1982). This potential feature of the single member plurality electoral system has always been evident in Canada (Cairns, 1968; Cairns, 1981). Even some advocates of the system have recognized this feature of its operation. See Duverger, 1964, pp. 382-4. In those elections. Labour won 60.5 per cent of the two-party vote and 80.4 per cent of the seats. For a fuller discussion of the relationship between constituency size and the exaggerative power of the electoral system, see Gudgin and Taylor, 1979, pp. 35-53. In order to simulate the process of non-partisan districting that would have to occur to produce those constituencies we used the 78 European parliamentary constituencies as our foundation. A set of rules which took into account the need to minimize the difference in constituency size, and to respect geographical contiguity and major local authority boundaries were devised in order to subdivide each Euro-constituency into two and four. This produced a set of 312 and 156 constituencies. A similar set of rules determined the combination of Euro-constituencies into 39 and 20 constituencies. Table 7 is based on votes cast in 1983. For further detail on the operation of the single member plurality system at European elections see Curtice 1985, pp. 155-8.

226

Proportionaiify and kaggeration m

tjJe

British Electoral $stdn?

29. This does not, of course, mean that the exaggerative quality of the electorai system at other elections has not been altered by the changing electoral geography. The exaggerative power of the European electoral system has declined in parallel with the decline in the exaggerative power of the Westminster electoral system, but has remained at a higher level (Curtice. 1985). If the European electoral system had been in operation in the 1960s it would have produced an exaggerative quality markedly greater than that of a cube law. 30. The departure from proportionality in Northern Ireland shown in Table 8, is due to the split in the Republican vote between the SDLP and the Sinn Fein. Consequently Unionists won three seats in 1983 despite a clear Republican majority in votes, one of which (Nenry & Armagh) they lost to the SDLP at the 1986 by-elections. 31. One can, indeed. think of the limiting case where this would have to be so. If in every constituency that it won every party won all the votes, then assuming equal sized constituencies and equal turnout, the election result would be proportional. 32. The threshold is sufficiently high to make it more difficult for the Alliance to win an overall majority. On the current electoral geography the minimum share of the vote the Alliance needs to win to have a chance of winning an overall majority is 42 per cent; for the Conservatives and Labour it is 38 per cent. Apart from the LiberaI/SDP Alliance and the SNP. the Alliance party in Northern Ireland is similarly treated by the electoral system. 33. See note 1. 34. For a more formal treatment of this point see Johnston, 1984, pp. 65-7. and the sources cited thereat. 35. These comments are based upon the figures for average monthly support in all the opinion polls produced by The Guardian (McKie, 1986). 36. Note also Hermens comment that, ‘a majority needs to be checked by an opposition of adequate strength, which the plurality system in single-member constituencies (. . .) does not always produce. Sixty per cent of the seats is enough for the majority to do its job.’ (Hermens, 1984: 29). Despite the reduction in the exaggerative quality of the electoral system, the Conservatives’ 1983 tally exceeded that proportion. 37. The use of the cube law was proposed by Hermens, one of the leading critics of proportional representation (Hermens, 1972). during the debate in West Germany between 1966 and 1969 as to whether to abandon its system of proportional representation. Hermens made his proposal in preference to the singie member plurality system because of the difficulties oi avoiding electoral bias in such a system (Bick, 1975). For further details see Jesse, 1985. pp. 184-91; Pulzer, 1983, p. 101. The square law was proposed for use in the Netherlands during the same period (Grosfeld, 1967; Theil, 1969). These proposals make it clear that the discovery of the cube law was not just of statistical or behavioural interest but was a means of legitimizing the exaggerative effects of the single-member plurality system. Interestingly, the cube law may have a separate German as well as an English ancestry. Hitherto, it has been written up in terms of the English literature, including the fact that David Butler in 1950 ‘rediscovered’ the original law as stated by Parker Smith to the Royal Commission on Electoral Systems in 1909 (Curtice and Steed. 1982: 25 2-3). This view is even to be found in the German literature (Bick, 1975). In fact, in his work in 1932 on comparative electoral systems Braunias notes as an empirical observation that the British relative majority system produces a cubic over-representation of the vote, although he does not generalize the case (Braunias, 1932: 181). It is unclear whether Braunias had consulted Parker Smith’s statement or not, but even so it is clear that the law was not entirely unknown before Butler’s work.

References BBUITN Guide to the New Parhhentury Constituencies, (Chichester: Parliamentary Reference Services, 1983). W, Bick, Mebrbeits Bir’dendeWablsyste~e und Wub~~eis~e~~~e~~~~g, (~Iejse~eim am Glam: Verlag Anton Hain, 1975). V. Bogdanor and D. Butler (editors), Democracy and Elections: Electoral systems and lheirpoiitical consequences, (London: Cambridge University Press, 1983). K. Braunias, Das Parlamenlariscbe Wahirecht: ein Hand&h fiber die Bildung der gesetzgebenden K6perscbaften in Europa II Band: Ailgemeiner Teil, (Berlin: Walter de Grayter. 1932).

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iZ1. Britton. ‘Recent Population Changes in Perspective’. Population Trends, 44: Summer 1986. pp. 33-41. D. Butler, ‘An Examination of The Results’, in: Nicholas (1951). D. Butler, The Electoral System in Britain since 1918, 2nd edn, (Oxford: Clarendon Press, 1963). D. Butler and P. Jowett, Party Strategies in Britain: A Study o/the 1984 European Elections (London: Macmillan, 1985). D. Butler and D. Kavanagh, The British General EIection of 1983, (London: Macmillan, 1984). D. Butler and A. King, The British General Election of 1964, (London: Macmillan, 1965). A. Cairns, ‘The Electoral System and the Party System in Canada’, Canadian Journal of Political Science, 1: 1968, pp. 55-80. A. Cairns, ‘The Constitutional, Legal and Historical Background’, in: Penniman (198 1). A. Carstairs, A Short History of Electoral Systems in Western Europe, (London: Allen & Unwin, 1980). Central Statistical Office, Regional Trends 1986, (London: HMSO, 1986). J. Chandler, ‘The Plurality Vote: A Reappraisal’, Political Studies, 30: 1982, pp. 87-94. R. Clogg. ‘Greece’ in: Bogdanor and Butler (1983). J. Curtice, ‘An Analysis of The Results’, in: Butler and Jowett (1985). J. Curtice and M. Steed, ‘Electoral Choice and the Production of Government: The Changing Operation of the Electoral System in the United Kingdom since 1955’, British Journal o/PoliticaI Science, 12: 1.982, pp. 249-98. J. Curtice and M. Steed, ‘An Analysis of The Voting’, m: ’ Butler and Kavanagh (1984). P. Dicken, ‘The industrial structure and the geography of manufacturing’, in: Johnston and Doornkamp (1982). A. Downs, An Economic Theory ofDemocracy, (New York: Harper, 1957). M. Duverger, Political Parties, (London: Methuen, 1964). M. Duverger, ‘Which is the Best Electoral System?‘, in: Lijphart and Grofman (1984). F. Grosfeld, ‘De kwadratuur van de democratische cirkelgang’, Vrij Nederland, 30 December 1967. G. Gudgin and P. Taylor, Seats, Votes and the Spatial Organisation of Elections. (London: Pion, 1979). A. Heath, R. Jowell and J. Curtice, How Britain Votes, (Oxford: Pergamon, 1985). F. Hermens, Democracy or Anarchy? A Study o/Proportional Representation, 2nd edn. (New York: Johnson Reprint Corporation, 1972). F. Hermens, ‘Representation and Proportional Representation’, in: Lijphart and Grofman (1984). B. Hogwood and M. Keating (editors), Regionai Government in England, (Oxford: CIarendon Press, 1982). C. Hughes, ‘The Electorate Speaks-And After’, in: Penniman (1979). E. Jesse, Wablrecbt Zwiscben Kontinuitiit und Reform, (Dusseldorfi Droste Verlag. 1985). R. Johnston, ‘Seats, Votes, Redistricting and the Allocation of Power in Electoral Systems’, in: Lijphart and Grofman (1984). R. Johnston, ‘Research Policy and Review 9. A space for place (or a place for space) in British psephology: a review of recent writings with special reference to the General Election of 1983’, Environment and Planning A, 18: 1986, pp. 573-98. R. Johnston and T. Doornkamp (editors), The Changing Geography oftbe UnitedKingdom, (London: Methuen, 1982). D. Kavanagh, British Politics: Continuities and Change. (London: Oxford University Press, 1985). P. Kellner, quoted in transcript of Weekend World, (London Weekend Television. 27 October 1985). M. Kendall and A. Stuart, ‘The Law of Cubic Proportions in Election Results’, British Journal of Sociology, 1: 1950, pp. 183-97. E. Lakeman, How Democracies Vote, (London: Faber, 1970). R. Lazarsfeld and N. Henry (editors), Readings in Mathematical Social Science, (Sew York: Free Press, 1958). A. Lijphart and B. Grofman (editors), Choosing an Electoral System: Issues and Alternatives, (New York: Praeger, 1984). I. McAllister and R. Rose, The Nationwide Competitionfor Votes, (London: Frances Pinter, 1984). D. McKie, ‘How Kinnock is passing the tougher tests’, The Guardian, 6 June 1986. J. March, ‘Party legislative representation as a function of election results’, Public Opinion Quarterly, 11: 1957, pp. 521-42 (reprinted in Lazarsfeld and Henry, 1958). D. Massey, Spatial Divisions of&our, (London: Macmillan, 1984).

228 H. D. D. H.

Proportiona&

and hqgeratron

in the British Electoral svstem

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