We know that population ageing will lead to the under-representation of young people within the democratic process. That representative democracies with mass franchises have only ever existed within populations with pyramid-shaped age distributions may be one of the hidden foundations of representative democracy. An ageing society, however, equals an ageing electorate – meaning that the people who will be affected for longest by the outcomes of the democratic process will have less say relative to people closer to the end of their lives. It is vital, therefore, that we find ways to ensure that young people are heard.

Generally speaking there are two main ways this can be achieved, although adopting one strategy does not preclude also introducing mechanisms based on the other. Firstly, we could look for ways to increase the representation of young people at the ballot box. Population ageing skews the age balance within the electorate significantly towards older voters, partly due to increased longevity, and partly due to the post-war and 1960s baby boomers edging towards retirement age. In response, we could increase the numbers of young people within the electorate.

This is the central aim of the Votes at 16 campaign. However, although lowering the voting age to 16 may be justifiable in terms of human rights, and in sending a powerful message about the value of young people to democracy, low cohort sizes for 16 and 17 year-olds mean it would not have a significant impact on the age balance within the electorate.

If applied to the electorate at the 2010 general election, the median voter would have been aged 45, rather than 46 as in the current system. But if we assume that 16 and 17 year-olds would have voted at the same rate as people aged between 18 and 24 (44%), then the median age of ‘actual’ voters would have been exactly the same, that is, 49 years old.

The electorate could also be increased by offering additional votes to parents. Children are affected by the democratic process directly, but are understandably not entitled to vote. Although not currently established in any political system, the ruling party in Hungary, Fidesz, proposed votes for parents in 2011.

But can parents really be expected to vote on behalf of their children’s interests? If so, it begs the question of why the system would be needed in the first place. Most members of older age cohorts within the electorate are parents (or grandparents); indeed, most members of younger cohorts are future parents. If individuals are deemed capable of voting on behalf of future citizens, can we not simply expect them to take into account the interests of future citizens in deciding upon their own preferences?

Given that young people’s disenfranchisement results from low turnout as much as it does from low cohort size, would compulsory voting be a worthwhile solution? Even with an abstention option on the ballot paper, however, compulsory voting compels young people (or any voter) to participate in an electoral process that they may not support. In Australia (which has compulsory voting) the Youth Electoral Study shows that, while most final-year secondary school students intend to vote when they reach voting age, barely half would do so if voting were not compulsory.

Guy Lodge and Sarah Birch recommend, however, compulsory voting for first-time voters only, with the main aim of not superficially increasing turnout, but rather socialising young people into engaging with the formal democratic process.

Compulsory voting does not of course solve the problem of non-registration: around 1 in 5 Australians aged between 18 and 25 are not on the electoral register, compared to around 1 in 25 of all eligible voters. In fact, the one sure thing we can do to mitigate young people’s political marginalisation is to oppose the government’s plans for individual voter registration, which will disenfranchise 10 million voters, predominantly young people in urban areas who move home frequently.

The first reform strategy will reduce ballot box inequality in a quantitative sense, but invariably leaves young people’s voting power vulnerable to cohort sizes. An alternative strategy would be to recognise that democracy needs young people, and therefore find ways to ensure that young people’s voices are permanently heard irrespective of the numbers.

As such, a small number of seats where the representatives were chosen only by young voters could be established within national and local legislatures. Young people would essentially have two votes: one within their constituency or ward, and one for the youth seats. This small group of representatives would inevitably become the voices of young people within the democratic system.

This would not mean that young people’s votes were worth double that of other age groups: if we assume that only people aged under 25 are able to ‘vote twice’, at the 2010 general election there would have been nearly 6 million electors for these seats in the House of Commons, compared to an average geographical constituency size of under 70,000. Less radically, legislatures could establish forums of young people, members in a non-voting, advisory capacity.

Most realistically, young people could be granted an ombudsman (Kirsty Schneeberger has advocated this idea in relation to future generations). A young person’s ombudsman would establish that, irrespective of the age profile of the electorate, the perspective of young people is vital to the democratic process and the legitimacy of the democratic system.

The government would be required to establish legally that the impact on young people of all policy decisions must be thoroughly considered. Currently, equality impact assessments require analysis of the impact of decisions on different age groups, but the assessments themselves are not binding, and it is not clear which age group should take precedence within the assessment in the event of a policy decision which benefits one age group at the expense of another. An ombudsman would have the power to challenge government decisions in the court where decisions have an undue impact on young people.

It is of course young people themselves that are best placed to address their relative disenfranchisement and its implications. But if we are to avoid young people opting out of the formal democratic process in increasing numbers, then as a society we need to be open to the kind of unorthodox solutions considered here. The core foundation of democracy as ‘one person, one vote’ is the key to its radical indefatigability, but how this is applied in practice has evolved over centuries, and must continue to do so in the wake of demographic change.