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Voter Turnout Decline and Stratification

The Changing Impact of Political Sophistication Indicators

Ruth Dassonneville

Département de science politique, Université de Montréal ruth.dassonneville@umontreal.ca

Marc Hooghe

Centre for Citizenship and Democracy, University of Leuven marc.hooghe@soc.kuleuven.be

Abstract

In numerous liberal democracies, levels of electoral turnout have declined in recent decades.

Thus far, however, it has not been investigated in a large comparative study what are the

consequences of this trend for inequalities in participation. In this article, we investigate

inequalities in terms of political sophistication in half a dozen advanced democracies. Our

results indicate that over-time, the participation gap between low and high politically

sophisticated citizens has grown wider. Furthermore, investigating the impact of the abolition

of compulsory voting in the Netherlands, we present suggestive evidence for the expectation

that it is decreasing turnout rates that elicit growing inequalities. The conclusion therefore has

to be that declining levels of electoral turnout coincide with a stronger stratification pattern,

thus limiting the representativeness of the electoral process.

Keywords: turnout; political sophistication; unequal participation; longitudinal analysis;

quasi-natural experiment

Paper presented at the ECPR General Conference Université de Montréal, 26-29 August 2015

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Introduction

The decline of electoral turnout levels that has been observed in numerous liberal democracies

constitutes an important challenge for representative democracy. In Lijphart’s (1997: 2)

words, “the democratic goal should be (…) universal or near-universal turnout”. Ideally,

elections offer a reliable and representative view of the political preferences of the population.

In its landmark decision Baker vs. Carr (1962) the US Supreme Court confirmed that electoral

rules should be designed in such a manner that the fundamental principle of ‘one person, one

vote’ is upheld. Basically this means that every citizen with voting rights should have the

same likelihood to impact on the designation of government officials and the development of

government policy, without any undue inequality as a result of location, gender, race, or other

background characteristics (Ansolabehere & Snyder, 2008). In order to ensure this principle,

accomplished turnout rates should be maximized. Declining turnout rates therefore imply the

risk that democracies are increasingly less likely to achieve the ideal.

Non-universal turnout is problematic because it is almost inevitably associated with unequal

turnout, with as a result that some groups of citizens are less likely to be represented in the

policy process than others. Time and again it has been shown that some groups of citizens are

more likely to turn out on Election Day than others. Most importantly, citizens’ resources

have a profound impact on their probability to vote. Those with a higher socio-economic

status, the higher educated and the higher politically sophisticated are more likely to turn out

compared to citizens without those resources (Smets & Van Ham, 2013; Verba & Nie, 1972).

Such inequalities in turnout also imply unequal possibilities to influence government policy

(Lijphart, 1997), there is a clear risk that some voices will simply not be heard and not be

represented. If higher turnout implies less inequality, the decline of turnout rates across

advanced democracies could be thought to result in increasing inequalities in who turns out to

vote and who does not. A stronger stratification of electoral turnout thus means that elections

will be less representative than in a situation with high turnout levels.

In this paper, we investigate the evolution of inequalities in turnout in a number of advanced

democracies. The theoretical and normative relevance of our analysis lies in the fact that we

can shed light on the consequences of this observed decline for representative democracy. A

basic quality requirement of representative democracy is that there is no systematic bias with

regard to the groups that are represented in the political process and those that are not

(Ansolabehere, Gerber, & Snyder, 2002). If the decline in turnout would be random across all

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population groups, even lower turnout levels could lead to an equally representative electoral

outcome. If the decline, however, is associated with a stronger pattern of stratification, this

means that some groups of the population will be more strongly represented in the electoral

outcome than others. Analysing inequalities in turnout, we focus on political sophistication, a

resource-variable of prime interest that has previously been found to be strongly related to

citizens’ probability of turning out to vote on Election Day (Smets & Van Ham, 2013). We

can assume therefore that if stratification occurs, sophistication will be an important

determinant.

Does declining turnout lead to growing disparities?

Across liberal democracies, there clearly is a decline with regard to electoral turnout rates.

While back in the literature of the 1990s, there was still some debate about the question

whether there really was a significant downward trend, in the more recent research literature

there seems to be a consensus that democracies are indeed being confronted with this

phenomenon (Gray & Caul, 2000; Hooghe, 2014). Blais and Rubenson (2013) note a sharp

drop in turnout rates in advanced democracies, from about 80% in the 1980s to about 70% in

the most recent elections. The observation of this marked decrease in turnout rates has

instigated a fierce scholarly debate on the sources of and reasons for the decline. Thus far,

various possible elements have been identified, ranging from the advent of post-materialist

values (Dalton, 2007a), a waning of citizens’ sense of civic duty (Blais & Rubenson, 2013;

Blais, 2000), changing electoral rules or the fact that elections are becoming less competitive

(Franklin, Lyons, & Marsh, 2004; Franklin, 2004). In this paper, however, our focus is not on

the potential determinants of the decline in voter turnout, but only on the potential

consequences of this process: if turnout levels decline, what does this imply for the

representativeness of the votes that have been casted? More specifically, we do not want to

make any claim about the question whether, e.g., changes in education level could play a

causal role in this process, as this would require a totally different analysis (see e.g., Gallego,

2009). Our research question follows a different logic: given an established trend of decline,

do we observe whether education – and political sophistication in general – becomes more

important as a stratification determinant of the electoral vote?

Electoral turnout is generally considered an indicator of the health and vitality of democracy

(Franklin, 1999; Lijphart, 1997). Low or decreasing turnout rates are hence considered a

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symptom that democracy is threatened, leading some scholars to suggest the introduction of

compulsory voting as a remedy (Hill, 2011; Lijphart, 1997). Reasons for academic concern

about low and declining turnout rates originate in a fear of inequality under low turnout.

Almost by definition, very high turnout rates do not leave much room for distortion, as the

sample of participating voters is almost identical to the population of citizens that have the

required voting age. In conditions of lower turnout, voters are – with respect to some

characteristics and attitudes – fundamentally different from non-voters. As a result,

participatory inequalities can have a huge impact on what voices are heard on Election Day,

and what policies will subsequently be implemented As we know that specific groups of the

population have specific policy preferences, this could lead to a major distortion of the input

the political system receives during elections (Citrin, Schickler, & Sides, 2003; Hansford &

Gomez, 2010; Pacek & Radcliff, 1995). A number of recent publications have nuanced

Lijphart’s claim that the policy preferences of voters and non-voters differ strongly (see e.g.,

the contributions to the special symposium edited by Lutz and Marsh (2007)). While these

differences are indeed rather small, those studies consistently observe some impact of turnout

on electoral outcomes. Furthermore, a fair number of studies has pointed out that differences

in turnout rates affect elite behaviour and the policies that are implemented as well (Griffin &

Newman, 2005; Hill & Leighley, 1996; Martin, 2003). The probability of such participatory

inequalities and disparities in representation, however, is thought to become smaller as

turnout increases, as Tingsten already argued in 1937 (quoted by Lijphart (1997: 2)). Low

turnout consequently implies more disparities.

What disparities do we observe when turnout evolves towards being less than universal? The

resource-model of political participation stresses that citizens who can rely on more resources

are more likely to turn out to vote on Election Day (Verba & Nie, 1972). As a result, the

higher social strata turn out at higher rates than lower status citizens do. This is clear from the

fact that higher income groups, but also the higher educated are generally found to have a

higher probability of voting (Leighley & Nagler, 2014; Wolfinger & Rosenstone, 1980). In

their meta-analysis of the individual-level determinants of turnout, Smets and van Ham (2013)

note a positive and significant effect of education on turnout in over 70% of the tests included

in their analysis. Further adding to the importance of resources in mobilizing citizens to vote

is the observation that political interest and political knowledge as well are strong predictors

of turnout (significant in 80% and 95% of all tests respectively). Clearly, there are strong

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indications that electoral participation is unequally distributed and that the more resourceful

are more likely to turn out to vote on Election Day than citizens with fewer resources.

Tingsten’s (1937) “law of dispersion” implies that disparities – for example due to citizens’

resources – will be higher as turnout is lower. Consequently, the decrease of turnout rates in

established democracies can be thought to be associated with growing disparities in the

stratification of who turns out to vote and who does not. If this is the case, declining turnout

rates might not only be indicating decreasing levels of support for the political system and

democracy in general. Additionally, those still turning out to vote would be ever less

representative for the electorate at large, and the signals that politicians receive on Election

Day are ever less indicative of the interests and positions of public opinion as a whole. A

number of scholars have previously reflected on the likelihood this scenario. Bovens and

Wille (2010, 2011), for example, have suggested that in the Netherlands, the education gap in

participation is increasing over time. This claim has been called into question, however, by

Hakhverdian and his colleagues (2012). Using the Dutch national election studies to analyse

changes between 1971 and 2010, they find that the impact of being higher educated on

turning out to vote has not grown stronger over time. Based on the same Dutch longitudinal

data, Stolle and Hooghe (2011) do not find indications for levels of education becoming a

stronger predictor of either emerging or conventional forms of participation over time either.

While the evidence in the Netherlands therefore does not seem to support the idea of a

widening education gap, research in other contexts in fact offers indications for such a pattern.

Gallego (2009), looking at over-time changes in the determinants of turnout in three advanced

democracies, finds that education is becoming a stronger predictor of electoral participation in

Germany and Sweden, but not in Norway. Armingeon and Schädel (2015) as well find some

indications of an increasing educational gap. They present a descriptive analysis of how the

ratio between the turnout among the high educated and the turnout of the low educated has

evolved over time and they find increasing inequalities in Italy, Germany, Norway and

Sweden. However, they detect no change in the United Kingdom, Denmark and the

Netherlands and even decreasing inequalities in Switzerland. Further, Persson et al. (2013)

have recently empirically substantiated Tingsten’s “law of dispersion” mechanism, as they

found factors such as income, levels of education and political interest to all become stronger

determinants of turnout in a low turnout election than was the case in a comparable high

turnout election in the Swedish Västra Götaland county. Clearly, the evidence for the

expectation that stratification patterns in turnout are increasing over time is somewhat mixed.

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Nevertheless, the decline of turnout rates in advanced democracies leads us to hypothesize

that – in line with the Tingsten’s law of dispersion – inequalities in electoral participation in

liberal democracies have increased over time.

In the remainder of this paper, we focus on investigating disparities in turnout due to citizens’

level of political sophistication. A regularly invoked and investigated indicator in this regard

is education. Not only are higher levels of education consistently found to increase citizens’

probability to turn out to vote (Blais, 2006; Leighley & Nagler, 2014; Smets & van Ham,

2013; Wolfinger & Rosenstone, 1980), scholars investigating a potentially widening

participation gap over time have also focused on the impact of education (Bovens & Wille,

2010; Gallego, 2009; Hakhverdian et al., 2012; Stolle & Hooghe, 2011). In line with the

existing literature, therefore, we will focus on levels of education. Educational levels are

thought to offer an indication of citizens’ cognitive skills, but also of how informed about and

interested in politics they are (Leighley & Nagler, 2014). As a more direct measure of

citizens’ motivation to acquire political information – which is an essential element of

political sophistication – we additionally include political interest as well in our analyses.

Looking at both levels of education an political interest, we follow a rich literature relying on

these two indicators for gaining insights in the effects of political sophistication (see, for

example, Dalton, 2012 and Lachat, 2007). While the education level could be seen as a stable

background characteristic of an individual, the level of political interest reflects the

involvement in the political process as a whole. In general, both indicators are highly

correlated as the highly educated, on average, also have higher levels of political interest

(Brady, Verba, & Schlozman, 1995). On a more pragmatic note, one can observe that both

indicators are routinely included in various data-gathering efforts, and they can be compared

across time and across societies.

Data and methods

For investigating the over-time evolution of inequalities in electoral participation, we have to

make use of survey data that cover an extended period of time as the decline of electoral

turnout is generally considered to be a structural process that stretches over decades. Such

data are provided by the European Voter Project, in the context of which time series of

national election surveys in Denmark, Germany, Great Britain, the Netherlands, Norway and

Sweden were harmonized and made publicly available (ICORE, 2005). These are the

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countries that started quite early with election studies (starting between 1956 and 1971) and

now can rely on a very long time-series of electoral survey data. We make use of these data

and complement them with more recent national election studies conducted in those

countries1, which allows tracing inequalities in turnout over multiple decades.2 Additionally,

we include the cumulative data of the American National Election Studies (ANES, 2012),

equally covering an extended period of time (1948-2012). A specific feature of these

countries is not just that they have a long lasting and reliable survey tradition, but also that

they are stable democracies, thus meeting all the requirements for this kind of analysis on

changes over time.

For investigating the impact of education and political interest on turnout, it is essential to rely

on individual-level data. These data come with an important limitation, as they suffer from a

bias towards over reported turnout (Karp & Brockington, 2005; Selb & Munzert, 2013). Such

a bias is due to the fact that voters are generally overrepresented in election surveys on the

one hand and due to a sense of social desirability, which leads respondents to falsely report

that they voted even though they did not turn out to vote (Selb & Munzert, 2013). The impact

of over reporting in election surveys, however, is reduced when validating turnout rates by

comparing them with individual level data in official turnout records. In the framework of the

current paper, validated turnout rates are included in the Norwegian and Swedish datasets, as

1. For Denmark we add the 2001 (CSSR, 2014a), 2005 (CSSR, 2014b), 2007 (CSSR, 2014c) and 2011 (CSSR, 2014d) national election studies. For the Netherlands we make use of the cumulative file of the Dutch Parliamentary Election Studies (Aarts & Todosijevìc, 2009) and we add the 2010 national election study (Van der Kolk, Aarts, & Tillie, 2012). For Norway we add the 2001 (Valen & Aardal, 2003), 2005 (Valen & Aardal, 2008) and 2009 (Valen & Aardal, 2011) election studies. For Germany we add the 2002 cross-sectional election study (Falter, Gabriel, & Rattinger, 2003), the first wave of the 2005-2009-2013 longitudinal election study (Rattinger et al., 2015), the 2009 cross-sectional election study (Rattinger, Roßteutscher, Schmitt-Beck, & Weßels, 2012) and the 2013 cross-sectional election study (Rattinger, Roßteutscher, Schmitt-Beck, Weßels, & Wolf, 2014). For the United Kingdom we add the 2001 (Clarke, Sanders, Stewart, & Whiteley, 2003), 2005 (Clarke, Sanders, Stewart, Whiteley, & Winters, 2006) and 2010 British election studies (Paul F. Whiteley & Sanders, 2014). For Sweden, finally, we add the data of the 2002 (Holmberg & Oscarsson, 2006) and 2006 (Holmberg & Oscarsson, 2012) Swedish election studies. 2. The starting point for the time series are: Denmark: 1971; Germany: 1961; United Kingdom: 1964; the Netherlands: 1971; Norway: 1965; Sweden: 1956.

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in these countries researchers have access to official information on whether a respondent has

actually voted or not.3

The core independent variables of interest in our analysis are respondents’ level of education

and their reported level of interest in politics. Levels of education were measured consistently

over time in each of the countries included in the analyses.4 In order to enhance the

comparability of the results for different countries, levels of education were standardized to

run from 0 to 1 in all samples. An additional advantage of this operationalization is that, in the

analyses, we are thus estimating the contrast between the lowest (0) to the highest educational

level (1). Investigating the impact of levels of education on turnout, it should be noted that

educational levels have been increasing in advanced democracies (Barro & Lee, 2013; Dalton,

1984, 2007b). Since we are not interested in the absolute level of educational effects, but

rather in the difference between lowly and highly educated groups (no matter what the size is

of these groups), this does not invalidate our design. In a similar analysis on the Netherlands,

Hakhverdian et al. (2012: 235) have claimed that changing proportions of the population that

belong to a specific category, do not have an effect on their results.

For political interest, the number of answer options is usually four but this number varies

somewhat over time in most of the countries.5 For reasons of comparability, we have thus

standardized political interest as well – to run from 0 to 1 in all election samples.

In order to avoid observing spurious effects when investigating the impact of education and

political interest on turnout, we also control for some routinely invoked predictors of turnout.

We control for respondents’ gender, age and age squared as well as religious affiliation when

available.6 Furthermore, in the analyses of turnout in Germany we add a dummy variable for

respondents living in East Germany after 1990, as turnout rates are (still) lower in the East of

Germany (Saalfeld & Schoen, 2015). Finally, we also control for the impact of race in the 3. Within the ANES time series, turnout has been validated in some elections, but not in others. For reasons of consistency we only make use of the non-validated self-reported turnout measure. 4. For all but two countries, we could do so distinguishing three educational levels (low, middle and higher educated). The British data only allowed consistently distinguishing between respondents with and without a higher education degree. For the Netherlands, finally, a higher level of detail could be used, distinguishing five different educational levels. 5. Germany switches to a 1-to-5 scale from 2002 onwards, in the British data this is the case from the 1997 election onwards. Further, in the Swedish case a three-point scale was used in 1956 only. For the Dutch data, political interest is consistently measured by means of a three-point scale. 6. This information was not included in Denmark, Norway and Sweden.

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United States, as this as well has previously been shown to be an important predictor of

individuals’ probability to turn out to vote (Leighley & Nagler, 2014).

Given the binary nature of our dependent variable (a respondent either reports to have voted

(1) or not (0)), we estimate a series of logistic regressions to investigate the impact of

education and political interest. Furthermore, as we are interested in investigating the over-

time evolution of disparities in turnout, we include a time variable as well. This variable takes

the value of 0 in the first election study included for a particular country, and increases one

unit every year. For assessing whether the impact of education and political interest has

changed over time, we include in the models interaction terms between education and time on

the one hand and between political interest and time on the other. We expect the main effect

of levels of education as well as political interest to be positive. Consequently, indications of a

widening gap would be offered by the observation of significant and positive interaction

terms.

Results

Before investigating the individual-level determinants of turnout, it is worth assessing to what

extent turnout levels have decreased in the set of countries looked at and whether such a

decrease is also reflected in the survey data. Figure 1 plots the over-time evolution of self-

reported turnout rates in each of the national election studies included in our analyses.

Furthermore, as an indicator for assessing the quality of these self-reported turnout figures,

Figure 1 also includes the official turnout rate, measured as a percent of the voting-age

population. Looking at the graphs indicates that – not surprisingly – relying on self-reported

turnout rates leads to an overestimation of the extent to which citizens turn out to vote on

Election Day. On average, the gap between the self-reported and official turnout rates

amounts to 12.5 percentage points and reaches a maximum value of 27 percentage points in

the case of the United States 2002 elections. Importantly, and despite this problem of over

reported turnout rates, trends in self-reported turn rates appear to capture quite well evolutions

in official turnout rates. Overall, the Pearson correlation between self-reported and official

turnout rates is 0.93. Only for Denmark and the Netherlands, we do not find a very strong

correlation between official turnout figures and the reported turnout in the election surveys.

This very high correlation might indicate that although over reporting obviously is a very

important problem, the relation between official turnout and report is rather constant across

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societies. Note that the official turnout rates presented in Figure 1 indicate a decline of levels

of electoral participation in all countries under study, with Sweden being marked by a late

decline, only visible from the late 1980s onwards. As turnout rates did not consistently

decline over time in Sweden, and given the centrality of such a decline for our argument, we

do not take the Swedish case into account in the remainder of our paper. If there is no decline

in Swedish turnout levels, we do not expect sophistication to become a stronger predictor for

stratification.

[FIGURE 1 ABOUT HERE]

As turnout levels have declined substantially over time in the countries under study in this

paper, we would – following Tingsten’s law of dispersion – expect the disparities in the extent

to which low and high sophisticated citizens turn out to vote to grow stronger over time. The

results of our analyses are listed in Tables 1 and 2 , where we present logistic regression

analyses explaining respondents’ self-reported turnout. Before looking at the interaction

terms, it is important to note that when estimating the analyses without interactions, the main

effects of our indicators of political sophistication (education and political interest) were

found to be positive and significantly related to the probability of turnout in all but one case,

i.e., Great Britain.7 Levels of education were not significantly related to the probability of

turnout in Great Britain. In all other countries, both levels of education as well as respondents’

reported level of interest in politics were found to significantly increase the probability that a

respondent turned out to vote on Election Day (with p<0.001). Given our research question,

these results only confirm a rich literature showing the importance of education and political

interest for explaining why some voters turn out to vote while others do not participate (Brady

et al., 1995; Smets & van Ham, 2013). Our main expectation, however is that the importance

of education and interest would become stronger over time. Assessing the interaction terms,

therefore, gives insights on whether or not the political sophistication gap in participation is

widening over time, as we have hypothesized. As is evident from the results in Table 1 and

Table 2, we indeed find indications of a growing sophistication gap. In Denmark and Norway,

we observe that education is becoming a stronger predictor of turnout over time – which

indicates that the gap between the low and the highly educated in these countries is widening

over time. Further, we note that political interest is becoming a stronger predictor over time in

Germany, Great Britain, the Netherlands and the United States – indicating that the

7. Results are not shown but are available from the authors.

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participation gap between low and high politically interested citizens is widening in those four

countries.

[TABLE 1 ABOUT HERE]

[TABLE 2 ABOUT HERE]

All in all, our results offer indications of the gap in electoral participation between low and

high politically sophisticated citizens growing wider over time in those countries where

electoral turnout is declining. These findings could be taken to indicate that the declining

turnout rates across advanced democracies are associated with a growing gap between who

turns out and who does not turn out to vote on Election Day. With respect to indicators of

political sophistication – such as levels of education or how interested one is in politics – the

electorate is hence becoming increasingly less representative of the public at large. More and

more, it is voters with high cognitive skills and a strong interest in politics who still turn out

to vote while citizens lacking those resources are increasingly dropping out of electoral

politics.

Even though turnout rates have decreased over time in all the countries looked at, we can only

assume the widening sophistication gap to be a consequence of decreasing levels of electoral

participation. In a next step, therefore, we assess more closely whether decreasing turnout

rates are indeed causally related to a widening sophistication gap in who turns out to vote and

who does not. Given limitations of the data, we will focus this test on one single country: the

Netherlands.

Additional Validity Test: A quasi-natural experiment

Having found that the sophistication gap in turnout widens over time, we now assess more

closely the validity of the claim that it is a decrease in turnout rates that leads to this widening

gap. In order to do so, we make use of the abolition of compulsory voting in the Netherlands

and how this change in electoral law has affected the sophistication gap in turnout. The

general expectation in the literature is that compulsory voting strongly increases electoral

turnout, especially among population groups with low levels of education (Hooghe &

Pelleriaux, 1998). The Netherlands offers an excellent opportunity, because an exogenous

element (changes in electoral law) had a profound effect on electoral turnout. By using this

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test case, we can be quite confident that the Dutch citizens not suddenly lost interest in

politics between 1967 and 1971, but that a change in electoral law was actually responsible

for the sharp decline in turnout levels (Irwin, 1974).

Between 1917 and 1970, voting was compulsory in the Netherlands (Andeweg & Irwin,

2009). The abolition of compulsory voting, and the transition to a system with voluntary

voting, resulted in a sudden decrease in turnout rates in the Netherlands. As Irwin (1974: 294)

has claimed, there is “little doubt that the change [in turnout] was due to the change in the

law and not to external factors”. This sudden decrease in turnout rates is evident from Figure

2, where we plot turnout rates in the Netherlands since 1946. The abolition of compulsory

voting is associated with a decrease in turnout rates from 95% in 1967 to 79% in 1971. Even

though turnout rates increased somewhat after the first election without compulsory voting,

turnout rates in the Netherlands after 1970 have continuously been at a lower level compared

to the situation pre-1970.

[FIGURE 2 ABOUT HERE]

This exogenously induced variation in turnout results in a quasi-natural experimental setting8,

that allows us to assess how a decrease in turnout impacts on the effect political sophistication

variables have on the probability of turnout. By doing so, we follow a series of recent

publications that all make use of changes in voting rules and variation in the timing of those

changes to assess the impact of turnout on electoral behaviour (Ferwerda, 2014; Finseraas &

Vernby, 2014; Fowler, 2013). For investigating the impact of the abolition of compulsory

voting – and the sharp decrease in turnout rates – we analyse the determinants of turnout

before and after 1970. We make use of election survey data from 1967 (Netherlands Institute

for Public Opinion Research, 2009), the last election before the change in electoral rules, and

from election survey data from 1971 (Aarts & Todosijevìc, 2009), the first legislative election

under voluntary voting. Pooling those two datasets allows us to compare ‘untreated’ citizens

(respondents in the 1967 election survey) with ‘treated’ citizens (respondents in the 1971

election survey). We expect the main effect of the treatment (i.e., the transition to a system

without compulsory voting) to be negative, as the change to a voluntary voting system has

reduced turnout. More importantly, we include an interactive term between the treatment and

political sophistication. We expect this interaction term to be positive and significant, which 8 . We label this is a quasi- and not a real experiment because the treatment was assigned to all subjects, instead of randomly assigning the treatment to some but not to others, who serve as a control group.

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would imply that the abolition of compulsory voting – and the associated drop in turnout rates

– has increased the sophistication gap between who turns out to vote on Election Day and

who does not.

As the 1967 Dutch election study only includes a limited number of variables, our quasi-

experimental test of the impact of political sophistication indicators relies on levels of

education only. We distinguish three educational groups (low, middle and higher educated)

and – as we did for the main analyses as well – we standardize this variable to run from 0 to 1.

Furthermore, we control for the impact of gender, age, age squared and religious

denomination in the analysis.

First, in Model 1 in Table 3 we only include the main effects of all independent variables. The

positive and significant effect of education confirms – for the Dutch 1967 and 1971 elections

as well – that higher educated voters are more likely to turn out to vote. Further, we observe

the expected effect of the treatment condition, the abolition of compulsory voting. ‘Treated’

citizens – i.e., respondents in the 1971 election survey – were significantly less likely to turn

out to vote compared to untreated respondents. Further, the results of Model 1 indicate that

the control variables behave as expected, with an indication of a curvilinear effect of age on

voting and Catholic and Protestant respondents being more likely to participate compared to

citizens without or with another religious denomination. We are mainly interested, however,

in whether or not the treatment alters the effect of political sophistication indicators, in this

case the level of education, on turnout. To that end, we include an interaction term between

the treatment and education in Model 2. As can be observed in the results in Table 3, the

results are in line with our expectations. We observe that the interaction term is positive and

significantly related to turnout, indicating that the effect of education on electoral

participation is strengthened under voluntary voting – when turnout is substantially lower. In

sum, our quasi-experimental test further substantiates the idea that a decrease in turnout rates

increases sophistication-based inequalities in participation.

[TABLE 3 ABOUT HERE]

Given that interaction terms in a logistic regression analysis cannot be straightforwardly

interpreted (Brambor, Clark, & Golder, 2006) and to gain insights in the size of the estimated

effects, we also calculated some predicted probabilities at values of interest. In Table 4, we

list the probability of turning out to vote for low (level of education = 0 ) and high (level of

education = 1) educated voters under compulsory and voluntary voting respectively. First, it

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has to be noted that the estimated probabilities of turning out to vote are substantially higher

than actual turnout rates, which is due to the fact that turnout is considerably over reported in

the 1967 and 1971 Dutch election studies as well. Despite this overestimation of the actual

turnout rates, we do note that probabilities to turn out to vote are lower under voluntary

voting. Importantly, the estimated predicted probabilities illustrate how the abolition of

compulsory voting in the Netherlands has resulted in a participation gap with respect to levels

of education. Both the lowest and highest educated groups had an estimated probability of

about 98% to report turning out to vote in the 1967 survey. In the 1971 survey, we note a

significantly lower probability of turning out to vote for both groups. This decline, however,

is much more pronounced for the lowest educated than what holds for the highest educated.

While the former group has an estimated probability of 85%, the estimated probability of the

latter group is still at 94%. Especially the lowest educational groups, hence, have dropped out

of electoral participation due to the transition to voluntary voting. As a result, we observe how

an educational gap – that did not exist previously – arises in the Netherlands as a result of the

abolishment of compulsory voting and the resulting decrease in turnout.

[TABLE 4 ABOUT HERE]

Discussion

Electoral turnout has declined significantly in recent years. The proportion of citizens taking

part in elections has declined quite strongly and some even predict this decreasing trend to

continue further (Bhatti & Hansen, 2012; Hooghe, 2014). By itself, this decline does not

automatically pose a normative problem: if turnout would be randomly assigned, one might

still expect that voters still offer a representative sample of public opinion. What we have

demonstrated in this paper, however, is that the decline of electoral turnout is not a random

phenomenon. In most of the countries for which we have a sufficiently long time series

showing a decline, we can observe that the long-term erosion of voter turnout coincides with a

more pronounced pattern of electoral stratification. More specifically, education and political

interest have become more important correlates of the decision whether or not to take part in

elections, which is evident from the significant interaction effect between time and indicators

of political sophistication.

15

Given the background of declining turnout levels, our research question was what this

structural trend implies for the stratification of electoral turnout. Theoretically, lower levels of

electoral turnout do not need to have consequences for stratification. If turnout was randomly

distributed across society, even a smaller proportion of voters might still be representative for

population as a whole. If it is not random, however, this means that a specific group of the

population receives more opportunities to let its voice get heard in the electoral process than

other groups. Our research question, therefore, is basically the same as the one Whiteley

(2011) already addressed: if levels of political participation decline, does this also imply that

participation becomes an instrument of only the ‘happy few’? Whitely arrived at the

conclusion that there is indeed a correlation: as the percentage of participants declines, the

remaining group of participants becomes ever more selective in terms of education level,

political interest, age and gender. To a large extent, our analysis of electoral turnout is in line

with this finding. For those countries where we can rely on sufficiently long time series to

document a structural decline of voter turnout, we do indeed observe that education or interest

become more important determinants of voting across time.

As some groups in particular are increasingly dropping out of electoral participation, there is a

clear risk that electoral results are less and less representative of the public opinion at large.

This is problematic because unequal turnout also implies unequal influence on who governs

and what policies are implemented. Even though previous research has indicated that

differences – in terms of preferences or issue positions – between voters and non-voters are

not that large, there are differences. And the fact that inequalities between who turns out to

vote and who is not are increasing implies that the impact of those differences on policy is

increasing over time.

As a counter-argument, it could be argued that the observation of the lower politically

sophisticated not turning out is actually a ‘blessing’ for democracy (Rosema, 2007). Indeed, if

especially the low involved and low interested do not participate in low turnout elections, this

might strengthen the impact of fundamental mechanisms of voting – such as accountability or

ideological proximity – on electoral outcomes (Rosema, 2007; Selb & Lachat, 2009). To

express it differently: the ‘quality’ of the vote might be improved if the least interested or

knowledgeable do no longer participate. Rosema (2007), however, has shown that such

positive effects of lower turnout are fairly limited, as even those with low levels of political

sophistication still manage to achieve a fairly good match between their preferences and the

party they vote for. Given these marginal ‘benefits’ of low turnout elections, we would claim

16

that the costs of unequal participation outweigh those benefits. As equality as such is an

important democratic ideal (Dahl, 1989) the mere observation of increasing inequalities in

turnout is worrisome for the future of representative democracies. In the normative debate on

the ‘one person, one vote’, attention is focused almost exclusively on the role of geography,

race and electoral districting. But one could make the case that inequalities that are due to

systematic differences in education level are equally troubling as they run counter to the basic

democratic ethos. As Whitely (2011) already observed: lower levels of party membership

seem to imply that being a member of a political party – and all the privileged access to power

this applies – increasingly become an asset of the happy few. Although self-evidently

electoral participation is much more widely spread across the population, we do observe the

same mechanism: lower electoral turnout, in practice, equals more strongly stratified turnout.

While the democratic ideal of ‘one person, one vote’ still is being upheld, increasingly some

groups do not cast their vote, and hence do not get their voice heard in the democratic

electoral process.

17

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Figure 1. Over-time trends in official and self-reported turnout

Note: Self-reported data as included in national election studies and official turnout rate, based on the voting age population (VAP). Source: IDEA database (www.idea.int).

23

Table 1. The (changing) effect of education and political interest on turnout – Denmark, Germany and Great Britain

Denmark

(1971-2011) Denmark

(1971-2011) Germany

(1969-2013) Germany

(1969-2013) Great Britain (1974-2010)

Great Britain (1974-2010)

Education Political interest Education Political interest Education Political interest

Female 0.128 0.135 0.081 0.106 0.215*** 0.223*** (0.079) (0.081) (0.088) (0.080) (0.038) (0.035) Age 0.131*** 0.132*** 0.061*** 0.061*** 0.0721*** 0.0734*** (0.019) (0.020) (0.012) (0.012) (0.008) (0.007) Age2 -0.001*** -0.001*** -0.000*** -0.000*** -0.000*** -0.000*** (0.000) (0.000) (0.000) (0.000) (0.000) (0.000) Roman Catholic (ref: none) 0.495*** 0.500*** 0.239** 0.229** (0.108) (0.108) (0.074) (0.077) Protestant (ref: none) 0.416*** 0.421*** 0.362*** 0.360*** (0.076) (0.076) (0.038) (0.036) Other (ref: none) -0.506 -0.524 0.111 0.113 (0.457) (0.456) (0.074) (0.079) East 0.010 0.039 (0.069) (0.066) Education (0-1) -0.341* 0.354** 0.181 0.829*** -0.003 0.204 (0.169) (0.119) (0.663) (0.187) (0.238) (0.118) Political interest (0-1) 3.215*** 2.871*** 2.772*** -0.170 2.259*** 1.498*** (0.164) (0.209) (0.623) (0.796) (0.158) (0.229) Time 0.003 0.005 -0.062*** -0.090*** -0.029*** -0.038*** (0.007) (0.009) (0.013) (0.016) (0.006) (0.005) Time * Education 0.027*** 0.018 0.007 (0.007) (0.015) (0.008) Time _* Political interest 0.014 0.087*** 0.026** (0.011) (0.025) (0.008) Constant -2.122*** -2.135*** 0.885 1.823** -1.394*** -1.153*** (0.498) (0.514) (0.650) (0.627) (0.185) (0.163) N 16,334 16,334 14,726 14,726 16,023 16,023 pseudo R2 0.124 0.123 0.159 0.169 0.115 0.116 Note: Unstandardized coefficients and standard errors (in parentheses) are reported. Standard errors are robust for election clusters in the data. Significance levels: * p < 0.05, ** p < 0.01, *** p < 0.001. Sources: Denmark (True European Voter database, Danish 2001, 2005, 2007 and 2011 national election study); Germany (True European Voter Database, German national election study 2001, 2005, 2009 and 2013); Great Britain (True European Voter Database, 2001, 2005 and 2010 British national election studies).

24

Table 2. The (changing) effect of education and political interest on turnout – The Netherlands, Norway and the United States

The Netherlands

(1971-2010) The Netherlands

(1971-2010) Norway

(1965-2009) Norway

(1965-2009) United States (1960-2008)

United States (1960-2008)

Education Political interest Education Political interest Education Political interest

Female 0.245*** 0.244*** 0.249*** 0.247*** 0.013 0.010 (0.044) (0.044) (0.038) (0.039) (0.037) (0.037) Age 0.061*** 0.062*** 0.107*** 0.108*** 0.102*** 0.106*** (0.009) (0.009) (0.011) (0.011) (0.007) (0.007) Age2 -0.000*** -0.000*** -0.001*** -0.001*** -0.001*** -0.001*** (0.000) (0.000) (0.000) (0.000) (0.000) (0.000) Black (ref: white) -0.096 -0.101 (0.054) (0.055) Hispanic (ref: white) -0.305*** -0.324*** (0.057) (0.058) Other (ref: white) -0.439*** -0.436*** (0.121) (0.119) Protestant (ref: Roman Catholic)

-0.287*** -0.287***

(0.057) (0.058) Other and none (ref: Roman Catholic)

-0.521*** -0.519***

(0.057) (0.057) Roman Catholic (ref: none) 0.170* 0.167* (0.080) (0.080) Protestant (ref: none) 0.810*** 0.808*** (0.091) (0.092) Other (ref: none) -0.505** -0.507** (0.161) (0.160) Education (0-1) 0.824*** 1.025*** 0.393* 0.679*** 0.808** 1.673*** (0.162) (0.086) (0.157) (0.091) (0.258) (0.094) Political interest (0-1) 2.008*** 1.696*** 2.476*** 1.755*** 1.605*** 1.204*** (0.102) (0.131) (0.208) (0.503) (0.088) (0.214) Time -0.009 -0.010* -0.015* -0.024*** -0.022** -0.017 (0.006) (0.005) (0.006) (0.007) (0.007) (0.009) Time x Education 0.010 0.012* 0.025*** (0.007) (0.005) (0.007) Time x Political interest 0.017** 0.029 0.012* (0.006) (0.018) (0.005)

25

Constant -0.536* -0.528* -1.950*** -1.746*** -2.746*** -2.933*** (0.210) (0.207) (0.358) (0.374) (0.268) (0.320) N 19,540 19,540 21,698 21,698 35,984 35,984 pseudo R2 0.097 0.097 0.091 0.092 0.150 0.149 Note: Unstandardized coefficients and standard errors (in parentheses) are reported. Standard errors are robust for election clusters in the data. Significance levels: * p < 0.05, ** p < 0.01, *** p < 0.001. Sources: the Netherlands (Dutch Parliamentary Election studies cumulative file (1971-2006) and 2010 national election study); Norway (True European Voter Database, 2001, 2005 and 2009 national election studies); United States (American National Election Studies, cumulative file 1948-2012).

26

Figure 2. Evolution of turnout in the Netherlands (1946-2012)

Note: Turnout rates (%) in Dutch parliamentary elections (1946-2012). Vertical line indicates timing of the abolition of compulsory voting. Source: IDEA voter turnout data (www.idea.int).

27

Table 3. The (changing) effect of education and political interest on turnout – with and without compulsory voting in the Netherlands Model 1 Model 2 Female 0.004 0.011 (0.116) (0.117) Age 0.607*** a 0.625*** a (0.176) (0.176) Age2 -0.059* a -0.061* a (0.025) (0.025) Roman Catholic (ref: none) 0.299* 0.300* (0.139) (0.140) Protestant (ref: none) 0.500*** 0.500*** (0.152) (0.152) Other (ref: none) -0.401 -0.400 (0.245) (0.245) Treatment -2.247*** -2.491*** (0.124) (0.158) Education (0-1) 0.604** -0.0892 (0.231) (0.342) Treatment * Education 1.138* (0.444) Constant 2.567*** 2.647*** (0.305) (0.309) N 9,041 9,041 pseudo R2 0.152 0.154 Note: Unstandardized coefficients and standard errors (in parentheses) are reported.

Treatment = abolishment of compulsory voting. Significance levels: * p < 0.05, ** p <

0.01, *** p < 0.001. a age was not measured as a continuous variable but as a

categorical variable, distinguishing 6 age categories. Sources: Dutch Parliamentary

Election Study 1967 (ICPSR 7361) and 1971 election from Dutch Parliamentary

Election Study Cumulative Dataset, 1971-2006 (ICPSR 28221).

28

Table 4. Predicted probability of turnout by level of education – comparing compulsory and voluntary voting systems Voting rule Level of education Pr(turnout) 90%-confidence intervals Compulsory voting Low (0) 98.57 [98.35 ; 98.78] Voluntary voting High (1) 98.39 [97.78 ; 98.92] Compulsory voting Low (0) 85.10 [83.37 ; 86.76] Voluntary voting High (1) 94.12 [92.41 ; 95.66] Note: Predicted probabilities of voting (in %) and 90%-confidence intervals. Predictions based on estimates of Model 2 in Table 3. All other variables set at the sample mean.