1 Introduction

The history of electoral suffrage is a history of the extension of the electorate (Congleton 2011). Today many people have trouble accepting ancient Greek democracies as ‘truly’ democratic. How can one talk of ‘the rule of the people’ if ‘the people’ only comprises a minor fraction of the population, namely males of a certain age and socio-economic status? Nowadays, the general rule is that everyone must be part of the electorate, independent of race, gender, or socio-economic status. One of the last barriers to everyone having a political say is age. Even though the age limit has been reduced to 18 years in most countries (CIA 2012; Steffani 1999), there is still a widespread consensus that a minimum voting age is necessary. Below this threshold, people are usually not deemed mature enough to cast a vote.

In this paper, we argue that this last limit to universal suffrage is not necessarily indispensable. We take the principle of ‘one person, one vote’ very seriously and conclude that its consequence, in principle, must be to endow children with the right to vote. The fact that children below a certain age are not able to fully understand political issues can be taken account of by letting their parents vote on their behalf. However such a proxy vote requires parents to be good electoral custodians. The paper also explores whether parents are likely to represent the interest of their children when casting their votes, or would simply multiply their own voting decision.

Both supporters and opponents of proxy votes for children hold strong beliefs about what parents would do if they had to cast a vote for their children. Unfortunately, there is little empirical data on how parents would actually use their children’s proxies. Since this issue is decisive for whether proxy votes for children should be introduced, in the conclusion we sketch out a field experiment to test parents’ voting behavior when endowed with a hypothetical vote for their children. Depending on the generated data, it should then be possible to finally decide in favor or against the proxy vote for children. This paper focusses mainly on the theoretical foundation for such a future empirical test based on constitutional economic principles.

The analysis is structured as follows. In Sect. 2, we argue that in general the franchise should be as universal as possible to avoid systematic discrimination of electoral outsiders, challenging the current limits to universal suffrage—above all, the exclusion of non-citizen residents, minors, non-humans and future individuals. In Sect. 3, we concentrate on the special case of the disenfranchisement of minors and describe—based on the proposal discussed in 2003 and 2004 in the German parliamentFootnote 1—a system in which parents would cast a proxy vote for each child which is mentally incapable of deciding on its own. This institution could close some intergenerational incidence gaps, but should not be confused with a solution to intergenerational distributional issues involving future generations. In Sect. 4, we first address the question how far parents can be expected to be good custodians; secondly, we critically assess potential alternatives to children’s suffrage. Since, as mentioned above, there is no reliable empirical data if parents would or would not make good electoral custodians, we conclude in Sect. 5 with the description of a possible field experiment to create the data necessary to decide in favor of or against voting on behalf of children.

2 Pluralism, democracy and the problem of electoral outsiders: justification and consequences of “one person, one vote”

2.1 The republican and the liberal tradition of democracy: from virtual representation to extending the franchise

Following Bennett (2000) and Rutherford (1998), we distinguish two separate traditions in Western democracy: the liberal one and the republican. According to the latter, the interests of every member of society are considered in policy making by ‘virtual representation’ (Bennett 2000, emphasis added). During the public discourse preceding any political decision the (rational) exchange of arguments forces policy makers to take a general perspective on the respective issue. By this mechanism, also the interests of those not being formally represented, receive adequate attention, and the final decision will reflect a generalizable perspective—similar to Rousseau’s (1762/1988) ideal of the Volonté Générale, the Founding Fathers’ understanding of democracy (Bennett 2000), or the more recent discourse ethics approach (see Habermas 1992).

The major problem with this ideal of democracy is that it rests on sufficiently identical interests of all members of a polity. Therefore, in modern pluralist societies, the second root of democracy necessarily gains importance. Central to this liberal—and widely accepted—ideal of democracy is that everyone is the best advocate of one’s own interests. In political contexts, this means that everyone must have the possibility to make him or herself heard and to have the power to influence decision making. In representative democratic systems, this most basically means “one person, one vote”. Consequently, the history of democracy is to considerable extent the history of extending suffrage (Congleton 2011). The middle class, poor, women, and blacks conducted long campaigns to get the same voting rights as relatively rich men, aiming at becoming (full) voters.

2.2 Consequences of limiting the political franchise: the political economy of electoral outsiders

Based on public choice models of democracy, depriving people of their right to vote is very likely to lead to their political marginalization. The cases of growing public debt or overstraining natural resources are prominent examples for how current voters shift burden on the young and the future generations, simply because the latter parties have no political weight in today’s policy making. Similarly, the neglect of the problems faced by foreigners residing in a country may also be the result of missing voting power (see Earnest 2003a, b).

The effective representation of non-voters interests by voters with different individual concerns only works if voters are sufficiently altruistic.Footnote 2 In pluralistic mass-democracies, we can neither assume homogeneous preferences nor general altruism. So, the model of democracy as public deliberation and implementation of the one general solution is not likely to characterize the reality of mass democracy. It seems more adequate to consider politics as competition between different political proposals and opinions. This is the perspective taken in the Downs-Schumpeter tradition of Public Choice.

In his seminal work Capitalism, Socialism and Democracy, Schumpeter (1942/1981) defines ‘the democratic method [as] that institutional arrangement for arriving at political decisions in which individuals acquire power to decide by means of a competitive struggle for people’s vote.’ In a representative system, different parties compete for the majority within an electorate. According to Schumpeter, this mechanism works similar to market competition. Producers only offer the demanded goods that satisfy consumers’ needs because it is the best way to maximize profits. By the same token, vote-maximizing politicians achieve this aim by offering ‘good policies,’ but only for the electoral demander (Schumpeter 1942/1981, see also Wohlgemuth 2003).

The median voter theorem yields similar predictions. Individuals who do not belong to the electorate do not contribute to the formation of the median position, the center of gravity. According to the theorem, integrating additional individuals with views differing from the median and non-symmetrically distributed around it would inevitably shift the median voter’s stance and thus influence political programs. Clearly, in such a system, the demand of those without voting power is mostly neglected. Political entrepreneurs will only target those able to offer something in exchange when creating their political offers.

2.3 Procedural safeguards against discrimination: universal suffrage and the democratic process

If we cannot rely on virtual representation, the positive Downs-Schumpeter model of democracy implies that if someone wants to affect political outcomes, he or she must have the possibility to participate in the process, i.e. be able to cast votes or otherwise provide support for candidates and parties. In pluralist societies, it is extremely difficult (if not impossible) to define specific outcomes per se as acceptable.

Nonetheless, people may agree on the procedure used to achieve outcomes. While there are no criteria to judge specific outcomes, it is possible to formulate criteria for the process leading to an outcome—a typical case of pure procedural justice, if we use Rawls’s (1971) terminology. In such a decision making environment, any outcome which was produced in accordance with a just process is legitimate (Buchanan 1999a, b; Vanberg 2011). Consequently, violating the procedural rules disqualifies the results. For Vanberg (2009), excluding members of a polity from decision making is such a violation.

Following contractarian tradition, Vanberg describes the ideal democratic state as an unanimously accepted ‘citizens’ cooperation’.Footnote 3 He and Buchanan emphasize the ‘gains from joint commitment’ that such a voluntary association offers. Unanimity at the constitutional level guarantees that only rules that are beneficial to all will be agreed upon.

The legitimization of such rules is derived from the sovereignty of the members of the joint political body. For constitutional economists, only rules that are in accordance with the preferences of those affected by them are acceptable (ibid., Buchanan 1999a). Rules must be approved and reformable by all members of a polity, i.e. by all those who are affected by collective decision-making. For example, if only men are allowed to vote and reject a proposal to introduce a quota for females in leading positions, this can hardly be called legitimate. But if an electorate including both, men and women, votes against such legislation by majority, the legitimacy of the very same outcome may be different.

We argued above that outcomes may change if the composition of the electorate affects the median voter. But this is not our main point. The central argument from a procedural perspective is not that a specific result can be expected, but that there is the chance for every affected individual to possibly alter the result. In modern pluralist democracies, every adult is granted the right to vote, although this does not grant the right to specific results. Excluding a party affected by a decision from the respective decision making process hence infringes his or her democratic rights, and thereby delegitimizes whatever outcome all others agreed on.

Consequently, any limit to political franchise calls for a very convincing justification, and, as is shown in the next section, some of the existing frontiers to universal suffrage have been challenged.

2.4 Current frontiers of universal suffrage

To sum up, the contractarian logic and the liberal model of democracy imply the following: (1) every member of a polity must have a vote, since he or she is affected by the decisions taken within it, and (2) each member should be able to vote for him or herself. Two additional questions arise: First, how to delimit the polity? Who is a citizen, and who is not? Secondly, should every citizen have the right to vote?

In most countries, citizenship is a necessary, but not a sufficient condition for having the right to vote. Some argue that not granting the franchise to temporary residents (e.g. people working or studying for a certain period of time in a country) is fully compatible with the above arguments for universal suffrage. Non-permanent residency implies that these people will leave the polity after some time. Why should such temporary residents have the right to vote and to affect political outcomes if they are not affected by the long-run effects of the associated policies? Thus, it may be argued that a polity should not grant the same rights to non-permanent residents as it grants to citizens (see Earnest 2003a, b). If temporary residents are unsatisfied with their condition, they can still choose the “exit” strategy. Voting by feet remains an option for temporary residents, and one that is usually easier to exercise for them than for ‘permanent’ residents.

The literature on the political integration of foreigners provides several arguments against the above view that non-permanent residents should be excluded from the franchise. This limit to universal suffrage is not indispensable, as for example the situation in the European Union shows: if a citizens of an EU-country stays for long in another EU-member-state, he has the right to vote in municipal elections, just as any national citizen (ibid.). Of course, this voting right is linked to EU citizenship, and does not include the right to vote on a national level.

Since our article focusses on voting rights for minors, we do not want to discuss this issue any further. For our purpose, it suffices to point out that voting rights are usually linked to citizenship.

Similarly, we cannot provide an in-depth analysis of the potential political franchise for future human beings or non-human beings, like apes.Footnote 4 The debate whether such entities can hold human rights at all is still in its infancy, not to mention granting citizen rights to them. As the case of non-permanent residents shows, the usual precondition for possessing the right to vote is citizenship. But to which polity will not-yet existing humans belong? For non-human beings, there is still the argument that voting is above all a mechanism to handle affairs among humans, despite the fact that human actions do have an impact on the living-conditions of non-human beings. Although these problems might be circumvented, it seems to be very unlikely that future human beings or non-humans will receive the right to vote in the near future.

For existing human beings, age is the second limit to universal suffrage. As often argued, the right to vote also implies the ability to execute this vote. According to this viewpoint, children lack—at least below a certain age—the maturity needed for political decisions, and consequently voting rights for children are not possible. The exclusion of non-permanent residents may be based on political and pragmatic arguments and at least in principle may be changed, but in the case of children, there is a natural limit namely their limited mental capacity.

Similar to the situation of mentally impaired adults, children do not have the same rights as mentally sane adults. Many decisions which are relevant for them—place of residence, religious affiliation, choice of school, acquiring property—are made on behalf of them, usually by their “natural custodians,” their parents. With increasing age, children may receive more and more rights, but full rights are only granted at the ‘age of majority’. A person’s age is of course not relevant on its own, but it is a widely accepted proxy for general maturity. Consequently, all democratic countries in the world set a certain minimum voting age, usually identical with age of consent (CIA 2012; Steffani 1999).

Nineteenth century arguments for limiting the franchise according to race, gender, and wealth were grounded in beliefs that these were useful criteria to separate the mentally capable from the incapable. After decades to centuries of severe emancipation fights, liberal democratic societies no longer accept the premise that women, black, or poor people are mentally less capable than the original white, male, and rich voter (Congleton 2011; Reimer 2004). For age, no similar emancipation movement is expected to take place,Footnote 5 leaving age as the final general limit to universal suffrage.

In the following section, we challenge the proposition that not being able to vote for oneself—as for sure is the case for the youngest—necessarily implies that some citizens must not possess the right to vote.

3 ‘One person, one vote’ and the case of minors: the specific case of voting rights for children

We now focus on the case for voting rights for minors. The number of affected individuals is considerable, amounting to some 20 % of a country’s population in most democracies. Unlike some other electoral outsiders, children are citizens and hence can be the carrier of civil rights like the one to vote. Children’s votes relate to several important political issues, above all intergenerational justice. Many see voting rights for children as a tool to achieve intergenerationally more equitable outcomes.

But, of course, at least below a certain age, children cannot cast informed votes and hence need a custodian. We suggest that minors receive the right to vote like any other citizen, and that parents execute this right on behalf of their children by casting a vote for each child in an election or referendum.Footnote 6 Arguing in favor of voting rights for children thus requires answers to a variety of questions: Who is supposed to vote on behalf of a child? How to organize proxy votes effectively? Can we be sure that electoral custodians will truly act on behalf of the minor whose vote he or she casts?

Although there is a relationship between intergenerational justice and children’s votes, it is more complex than the public debate (e.g. around the 2004 decision in the German parliament) suggests.Footnote 7 Voting rights for children can address some intergenerational distributive issues, but children’s suffrage is not an adequate tool to solve all intergenerational equity problems.

3.1 Voting rights for children as a tool for intergenerational justice: the consequentialist motivation and its limits

A widely used and accepted justification for including children in the electorate is that voting power for minors would be a powerful tool to end several inacceptable forms of intergenerational discrimination (Arndt-Brauer et al. 2003; Löw 2003; Peschel-Gutzeit 1999). Current phenomena like climate change, increasing public debt and pension systems that put more and more pressure on the young are, in this perspective, nothing but the result of the gross power imbalance between the young and the old. If, as currently is the case, the median voter is older than the median member of the polity—due to the asymmetric cut of the minimum voting age—political proposals and decisions tend to have an “intergenerational bias” on the expense of the young and unborn without political say. So in accordance with the Schumpeter-Downs model of democracy, burden shifting on the expense of the young and the future generations is to be expected.

But, as some argue (e.g. Holste 2005; Goerres and Tiemann 2009), voting rights for children are no guarantee that less public debt or less strain on the environment will occur. Parents voting for their children could also lead to more public debt, if the votes of the minors are used to support public programs for more schooling or more childcare. Similarly, the political demand for more public investment might also increase environmental degradation—quite the contrary of what the promoters of children’s suffrage would want.

Nonetheless, if the interests of minors are represented correctly by electoral custodians, policies that harm the interests of children should be harder to implement. So voting rights for children in principle may help addressing problems where burden shifting on expense of minors can be expected.

Of course, there might be the chance that all currently living are abusing their voting power against the interests of the unborn. This would also occur if electoral custodians do not use their child’s proxy votes to represent the child’s interest at the ballot box, but use it to multiply the impact of their own myopic preferences (ibid., see also Sect. 4.1). Moreover, voting rights for children do not give a voice to the not-yet-born. If a society wants to give the interests of non-yet-existing individuals their weight too, other tools are needed (see Sect. 4.2).

To keep these two aspects separate, Tremmel (2009) introduces two different concepts of intergenerational justice: Intertemporal intergenerational justice applies to contexts where acts of the currently living affect individuals not yet born, i.e. related to (distributive) issues arising between the ‘present generation’ (everyone living at the moment) and ‘future generations’. Temporal intergenerational justice is concerned where different age groups overlap within an existing “intertemporal” generation, for example existing minors (below 18), working adults (roughly between 18 and 65), and living retired people. This is the intergenerational justice context in which we see children’s votes: they are a tool to represent the interests of current minors—nothing less, nothing more.

Children’s suffrage via proxy has the chance, in accordance with the Downs-Schumpeter model, to alleviate temporal intergenerational justice problems arising between minors outside and adults inside the electorate.

3.2 Why children should get the right to vote: the deontological justification of voting rights for children

The procedural understanding of democracy implies that society has the duty to give every member of a polity the right to vote. For adult non-citizens living in a polity, the problem arises if he or she may be granted a right which is reserved for citizens only. For children, the problem of citizenry does not arise.Footnote 8 In many contexts other than voting, children do have rights, and their parents or the state have the duty to ensure that these rights are respected. For example, in most countries a child has the right to education, which either must be organized by the parents or is publicly provided. Apart from having rights, children even have duties and are held responsible for the consequences of certain willful misconduct.

Munn (2012) points out a fundamental discrimination against children if one compares voting age restrictions with the age limits for children becoming legally responsible for their actions. In most countries, the voting age is set at 18 (ibid., p. 147). Criminal responsibility, however, comes significantly earlier, most countries have set it at age 10 (some even consider seven the appropriate age), increasing the degree of responsibility again around age 14 (ibid., p. 144, 151). This, according to Munn, appears inconsistent: despite the fact that criminal acts have effects on a smaller number of people (minimum two) while voting per definition has an impact on the whole of society, the mental capacities involved in both cases are not very different.

The fact that children do have rights in other contexts and that they are considered as responsible actors in non-political contexts implies two things: First of all, children are citizens too, and hence not granting them the same rights like any other citizen calls for justification. Secondly, children by and large do have the mental capacity needed for political decision making before they reach the age of 18.Footnote 9 From a psychological perspective, lowering the voting age to 14 years does not seem exaggerated,Footnote 10 or even the introduction of a flexible limit such a the following: As soon as a child declares his or her will to take part in elections or if he or she passes a maturity test, then the child receives the right to vote (ibid., p. 155).

Even if the minimum voting age is lowered or made flexible—and especially if the current fixed age limit of 18 is maintained—a considerable number of children will not have the (mental) abilities or knowledge to make a political decision and hence are not capable of executing a voting decision.

However, not being able to execute a right does not necessarily imply that one must not possess the right. Below a certain age, a child might not be allowed to buy and sell property of significant value, but it can own it (Olsson 2008). Purchasing decisions can be made on behalf of the child by his or her parents. By the same token, one can argue that in those cases where a child is for sure not able to execute the right to vote, he or she nevertheless possesses the right, but it is executed on behalf of the owner of the right by the respective legal custodian.

Similarly, our conclusion in the case of voting rights is that children are citizens, and hence should have the same rights as any other citizens. Depriving them of the right to vote is illegitimate. Even if a child cannot execute this right on his or her own, each child has a legal custodian (usually two custodians, namely the parents), who can execute the right on behalf of the child. Giving children the right to vote fixes severe legitimization problems of political decisions as far as the children’s interests are concerned—unless we must expect vote abuse by parents, an issue discussed below.

3.3 Parents voting on behalf of their children: a proposal

We next sketch out how such a proxy vote system could look in order to clarify several relevant questions of implementation. Reimer (2004) distinguishes among three types of child suffrage. Firstly there is the original child’s vote: the age limit is abolished, and children directly get the right to vote, without appointing any legal custodian. Secondly, there is a so-called original parents’ vote. Parents receive additional voting power, proportional to the number of children. Thirdly, Reimer defines the derived parents’ vote, meaning that children receive voting power, but parents vote on behalf of their underage children.

As argued above, the first suggestion must clearly be rejected in its totality (ibid.). Lowering the voting age is a feasible option which was chosen in many countries in the past, but is impossible for babies and young children who are not capable of formulating their own political opinions. The second proposal must be rejected, too (ibid.; Holste 2005). Multiplying the influence of specific groups of a polity is against the fundamental principle of ‘one person, one vote’. Even though families play an important role in the sustainment of any society, manipulating electoral principles in their favor is illegitimate, and in many countries this would even violate the constitution (for the German case, see Goerres and Tiemann 2009).

Hence, only the third approach remains a legitimate democratic option. With respect to the third option, there are several ways for implement voting rights for children. Oebbecke (2004) summarizes the options for the ‘standard case’ of one child with two parents being endowed with one vote, respectively several children in a two-parent family. One solution is to (1) let both parents come to a joint decision in advance of the elections, which is—in our opinion rightfully—dismissed due to its violation of the electoral secret. We are also skeptical concerning the proposal of letting mothers and fathers rotate in different ways, either (2) giving the mother generally the execution right for the first born, the father the one for the second born, and so on, or (3) rotating among elections. Solution (2) creates, among other problems, an enormous imbalance in case a pair of parents has an odd number of children. Idea (3) seems rather complicated in execution.

Hence, we hold it to be the most elegant and least complicated solution to split the child’s vote in two, such that each parent has the duty of executing half a vote on behalf of the child. Naturally, single mothers or fathers would have the full vote since they have complete parental authority. So in the end, if two parents have three children, each parent casts three half votes, one on behalf of each child.Footnote 11

For orphans or foster (or adopted) children, the respective legal custodian would have the right, but also the duty, to cast the child’s vote. This follows from two parallel thoughts. First, every child has the right to vote, independent of who his or her legal custodian is. Since every child without parents has a legal custodian, then the right to execute is correspondingly transferred to the legal custodian. This, secondly, is the way a custodian handles a ward’s rights concerning non-political decision making, like which school a child attends, or concerning medical treatment, etc. One problem thereby arising might be the case of one orphanage manager being legally in charge of a large number of minors. But in such case, the manager will not be the only person in charge in the respective institutions, and vote execution can be split among the responsible adults, such that every child’s full vote finds one representative.

It is possible to construct hypothetical cases where one person is allowed to cast the votes for a huge number of children, abusing all of which in his favor. Such potential extreme cases are, as we see it, not a fundamental argument against children’s votes. The fact that some people illegally sell their votes (see e.g. Durante 2014 for a description of vote buying by the Italian mafia) does not lead to the abolition of voting as such, but rather suggests that well-designed measures are needed to minimize abuse. The only way of avoiding any abuse is by abolishing voting as such, including the abolishment of all the benefits we attribute to voting: the democratic control of government. Similarly, in very special cases, proxy voting may lead to abuse; this is no reason to abandon children’s votes as such, since they would give children their fair political weight. The most relevant question is whether proxy voting can be expected to work in the standard case, i.e. will parents be good custodians for the interests of their own children?

4 Challenges and alternatives to children’s suffrage

4.1 The central problem of children’s votes: will parents make good electoral custodians?

If parents are supposed to vote on behalf of their children, can we be sure that they will use these votes in their children’s best interest? Recently, Bertelsmann Stiftung, one of Germany’s leading political think tanks, published a study which explicitly addressed the question if parents are more short term oriented than the rest of the population (Vehrkamp et al. 2014). Especially relying on “morphological depth interviews” conducted by Rheingold Institute, the researchers found out that—at least for this German sample—parents revealed a stronger short term orientation than childless interviewees (ibid.). This, the study concludes, seems to be the results of the pressing everyday problems parents are facing, such that they are putting more weight on solutions for the more immediate problems at the expense of long-term interests. For example, parents might rather vote for better public childcare, even though such “pro families” policies might be financed via additional public debt. Concerning the potential of voting rights for children—institutionalized as described in this article—the authors reject the conclusion that such proxy votes would increase the long-term orientation of politics. On the contrary, they even expect more short-sightedness in politics if parents could vote for their children. This study implies that despite being well intended, children’s votes would worsen the situation for children in the long run.

Apart from the above cited study, at least to our knowledge there are no other empirical works directly addressing the question if parents would make good electoral custodians. Nonetheless, there are several reasons why it seems unlikely to us that parents would make bad electoral custodians who would abuse their children’s votes.

If having children negatively affects a person’s long-term orientation, does this imply that childlessness is better for a society in the long run? We are sure that this is not the conclusion the authors of the study want to imply. Children are the most vital element for a society to exist in the long run at all. Perhaps the parents’ short-term orientation should be interpreted as a result of societal circumstances in which having children leads to the problems the parents ask to be solved. In the concrete case, the existing lack of day-care centers or similar pro-family policies in Germany (see e.g. Arndt-Brauer et al. 2003; Peschel-Gutzeit 1999) can be explained as a result of policy making which does not take the interests of children and parents sufficiently into consideration.

Currently, it is the parents who bear most cost of child rising, For example in the US, the expenses for a 17-year old high school child amount to nearly USD 300,000 in a two-parent, middle-income household (authors’ calculations based on USDA 2011). At the same time, the financial conditions for child raising have become worse: Folbre (1994) shows that since the 1960s, US public spending targeted towards children has decreased relatively to spending targeted towards the elderly. This, as she argues, has largely contributed to increasing the poverty risk, especially for single mothers. The fact that parents may ask for more public aid is thus not necessarily a sign of over-proportional selfishness, but may just be a reaction to the problems that parents bear considerable cost for society by raising tomorrow’s workers and taxpayers, while the childless benefit more from the system, proportionally-speaking.

To sum up, it seems highly unlikely that parents would be willing to sacrifice consumption opportunities, care about their children’s success in school and in their professional life, all the while willfully adding to one severe problem for their own offspring, namely public debt. We argue that it is more likely that parents, while supporting public spending on child programs, do not wish to see that funding come from debt but from the redistribution of tax burdens and benefits.

Of course, this hypothesis requires empirical testing. A systematic study is needed as to whether, in general, parents’ opinions on public programs, public debt and long-term orientation differ from average population. The data from Vehrkamp et al. (2014) unfortunately are too general and speculative in this respect. Even if it political priorities change towards pro-family policies, this may be the result of a decision making process in which the preferences of all affected parties affect outcomes, being perfectly in line with a procedural understanding of democracy.

Additional support for the hypothesis ‘parents make good advocates’ comes from Washington’s (2008) findings. Washington examined how men’s voting behavior in the US is modified once they become the fathers of one or more daughters. Her results show that with each daughter, the fathers’ probability to vote left-of-center significantly increases. Not only did she demonstrate a statistical correlation, but she also put forward a convincing theory of a two-fold causal effect. First of all, this observation can be explained by the fact that more left-wing candidates running for Congress tend to hold views that are more compatible with female emancipation, whereas conservative politicians will more likely embrace traditional role models. One can assume that fathers start taking such issues into consideration because they feel responsible for their daughter(s). Consequently, they shift their electoral decisions to the left compared to their initial position in order to push politics into a pro-woman direction, better reflecting the interests of their female child respectively chilren. This first hypothesis is compatible with the one upheld by supporters of child suffrage according to which parents do genuinely take into consideration the interests of their offspring, rather than, as suggested by opponents, parents just multiplying their own original views.

Yet, if there is a significant effect on fathers’ voting behavior, shouldn’t this lead to a shift in electoral results on the left–right spectrum? We do not believe so, for three reasons: first of all, although the effect Washington identified was statistically significant, its overall impact cannot be considered dramatic considering the total size of the respective electorate (i.e. significance must not be confused with magnitude). The point we deduce from her results is the following: these results support the hypothesis according to which parents take their children’s interests into consideration; we are not primarily concerned about the effect on the distribution of votes on the right-left-spectrum. Secondly, Oswald and Powdthavee (2010) show similar, but opposite effects for parents who have male children, such that in total, even larger effects should simply level out. Thirdly, Schumpeter’s theory predicts (see Sect. 2.1, Peschel-Gutzeit 1999; Göll 2004) that policy makers should, rationally maximizing votes, all offer more pro-family and long-term oriented programs and policies, whatever their ideological position on the political spectrum.

The second line of thought advanced by Washington (2008) is that one cannot rule out that daughters (as well as sons) actively participate in influencing their fathers’ political views. This would suggest that children are indeed able to formulate their own political opinions, supporting the claim of endowing them with indirect voting rights. Whether only one or even both hypotheses hold true (we think that both sound plausible): Washington’s results do support the normative claim in favor of the right to vote for children, thus reducing the strength of objections.

The last study discussed in this subsection is the one conducted by Meirick and Wackman (2004). Both scholars examined how political information campaigns undertaken in schools affect students’ political knowledge. The overall result is that one indeed observes positive effects on students’ information levels. Additionally, it is important to recognize that the feared widening of the relative knowledge gap (i.e. children from better-off families might gain much more than those from underprivileged families) was not observed; on the contrary, in many cases the relative gap even closed (ibid.).

In all, not only did all children improve their political knowledge, but those farthest away from political participation gained most. This should help reduce the initial de facto differences in power of political expression between the ‘rich’ and the ‘poor’. This effect is also desirable from the standpoint of democratic theory since it reduces the actual differences in voting power execution. Meirick and Wackman’s results show that explicit political education of students at the age of twelve makes them politically more mature. If it is possible to raise children’s political maturity, then it becomes more likely that they could effectively impact their parents’ decision as to whom to vote for when exercising their child’s right to vote.

4.2 Alternatives to children’s suffrage and their drawbacks

A critic of voting rights for children might argue that many of the problems children’s votes address could be solved by other institutional solutions, which might be more effective and at the same less prone to abuse than proxy votes. Such tools hence focus on the consequentialist justification of children’s votes, namely their potential to achieve certain policy outcomes in accordance with intergenerational distributive goals. Despite our focus on the procedural argument in favor of children’s vote, this discussion is important, since the consequentialist perspective cannot be simply ignored.

We distinguish two approaches to deal with intergenerational issuesFootnote 12 in democracies: the first one aims at adding certain institutions to the existing political system, while the second one proposes changes in the way individual votes are fed into the existing system. Van Parijs (1998, 2011) offers a detailed overview of both attempts. Concerning the first, he discusses models where some form of ombudsman, committee or parliamentary council is supposed to defend the interests of the young and future generations, counter-balancing the short-term orientation of the existing democratic system.

The problem with all these solutions is that it seems hard to install a truly powerful counter-weight given the political forces in place. The debt-brakes in Switzerland and Germany may be an example for such an institutional solution, but their success is not yet assured (for the fate of similar constructs in the US in the 1970s and 1980s, see Ellwood 1988), and major problems such as health care, education, or environmental degradation still remain unsolved. Any really powerful political organ systematically tackling these issues must be strong enough to effectively overrule, or at least level out, the decisions made by other democratic bodies, which in the end may be contrary to well-established concepts of democratic rule. Such organs must act paternalistically by definition, and repeated overruling of e.g. parliamentary decisions might undermine the support for such institutions.

The second class of solutions follows a similar direction with respect to children’s suffrage affecting the voting power of the underprivileged. Brighouse and Fleurbaey (2010) argue for example that it would be best to grant voters voting powers proportional to the stakes they have in a specific issue. With respect to age differences this may call for endowing younger voters with more voting power and the elderly with less (see Van Parijs (1998) for a detailed discussion), because the younger have more lifetime ahead of them and hence are more affected than seniors by current political decisions.

From a theoretical perspective, this proposal sounds plausible and even fairer than giving a child the same voting power as a senior. But concerning implementation, the most obvious drawback is that there are no objective criteria for deciding how much voting power a person should receive concerning different issues. Apart from this, it undermines an idea which is of constitutional importance for Western democratic societies: every individual is equally important, independent of a person’s particular life circumstances. Individualized voting power goes exactly into the opposite direction, without providing effective and generally accepted discrimination principles.

Additionally, if one takes the proportional voting power principle seriously, it is actually incompatible with any age limit. Children must necessarily get voting power, too, and even more than those above the age limit (due to their higher life-expectancy). But since they cannot directly exercise their right to vote, the question of electoral custodians arises in the same way as with the system accommodating children’s suffrage suggested in Sect. 3. Given the severe drawbacks of the presented alternatives, we thus conclude that the children’s right to vote as suggested in Sect. 3 is the best solution if changes are to be made at the electoral level.

5 Conclusion: a conditional recommendation of children’s votes and a proposed field experiment

The first conclusion of our analysis is that if we take seriously the principle “one person, one vote”, then children should be enfranchised. The main problem with children’s right to vote is that the political immaturity of children calls for electoral custodians, for which parents naturally qualify. Unfortunately, whether parents are able to make electoral choices for their children that are genuinely distinct from their own has not yet been resolved and calls for a systematic empirical investigation.

Overall, we identified three remaining questions: (1) Do parents systematically differ in their attitudes towards certain policies, especially those with strong long-term effects? (2) Will the right to vote for children shift election results significantly to the left or to the right? (3) Will parents, when deciding how to use their children’s ballots, make a choice that is genuinely different from their own?

The first question is important to assess whether child voting would systematically induce long-term orientation in general politics. So far, we can only argue that it is not likely that it would lead to a worsening of the situation as compared to the status quo. Even though this aspect does not directly relate to proxy votes for children, it would strengthen the argument for children’s votes if one could rule out that most of the electoral custodians are strongly short-term oriented. The respective findings of Vehrkamp et al. (2014) are a start, but do not answer one central question: Is parents’ short term orientation the result of genuinely different time preferences, or rather the result of the difficult circumstances in which they raise children? To us, the latter explanation makes more sense from an economic perspective.

Regarding the second question, we believe that the answer is ‘no’. The reason for asking the second one is similar as for the first one: Despite the procedural-deontological justification, systematic effects on party shares in elections are too important to be bluntly ignored. Regarding the third and most important question, we expect an affirmative answer.

Of course, the best, however well-reasoned, guess does not suffice as an answer. Hence we suggest three empirical investigations to shed more light on these issues. For the first one, data on voting behavior needs to be analyzed accordingly. Concerning the second and third question, we plan to run a test vote during an actual election in Germany. Such a survey would be based on an after-election survey asking the following questions to parents of minor children.

First, we would ask the parent which party he or she chose for him- or herself. Secondly, we would present a couple of political topics, e.g. reforming the pension system, reducing public debt, or more effort for climate change prevention, and let the parent state how important he or she considers each policy field. Then, the parent would have to give the age of all minor children, and finally be asked to evaluate the importance of the very same policy fields as presented before from the perspective his or her children. After this, each parent is asked about her opinion on voting on behalf of her children, and if she would discuss the decision (separately) with each child before the election. Here, we expect the likelihood to increase with a child’s age. Finally, each parent should execute half a vote on behalf of each child (one vote for single parents).

A crucial point is that looking at a parent’s vote and the one cast for each child is not enough. What matters for a children’s proxy vote to effectively make the children’s voice heard is that parents do not simply multiply their decision, but make a genuine and as far as possible independent decision for a child. Finding—or not finding—significant differences between a parent’s own choice and the vote cast for a child is not enough to answer this question about motivation, even though the results are interesting concerning how far the election result would differ. Parents might just want to use the additional vote(s) to diversify their decision, a phenomenon observable in the two vote system applied in Germany’s federal elections (see Gschwend 2007).

Even if there are no significant differences, this behavior might not imply vote multiplication, but be the result of two different decisions leading to the same conclusion: a parent might prefer a party for their stance on foreign policies, but at the same time think the same party has the most attractive education policy which is very important for the child. For this reasons, we suggest—as described above—asking parents how important they consider certain central policies for themselves, but also for their oldest child (limited to this one child for methodological reasons). Even though again we would only look at certain outcomes, these are closely related to preferences and hence motivational aspects.

If we find that parents judge the relevance of policy from their children’s perspective completely different than from their own, children’s suffrage can and should be the tool used to heal the current defects of the electoral system, based on the arguments presented above. But, if the empirical investigation into parents’ motivations strongly suggests that adults prefer to multiply a decision taken only in their own interest, the suggested children’s voting institution would miss its declared aim and undermine the constitutional basic principle of ‘one person, one vote’. In that case, from a constitutional economic viewpoint, the right to vote for children should be rejected.

To sum up: whether the right to vote for children may legally be introduced or not depends on whether parents are able to genuinely represent their children’s long term interests. In the end, this issue requires further empirical investigation.