The 2013 election was probably the first in Australian history in which half of the votes were cast by electors aged fifty or over. Although only 47 per cent of people on the electoral roll fall into that age group, the lower voting rate among young adults means it’s highly likely that the older group’s share of actual votes topped 50 per cent.

Twenty years ago, when Paul Keating fought back to defeat John Hewson in the 1993 election, only a third of adults entitled to vote were aged fifty or over. By 2004, when Mark Latham faced John Howard, the figure had grown to 42 per cent. It will continue to creep up, slowly but steadily.

While the challenges posed by an ageing population attract a great deal of attention, this milestone is a reminder that little notice has been paid to the implications of an ageing electorate.

An older electorate complicates and probably narrows the options the federal government has for dealing with an ageing society. For evidence, look no further than the experience of the Howard government. Faced with the policy pressures of demographic change, treasurer Peter Costello frequently asserted that the federal government needed to curb overly generous benefits for the elderly. But John Howard, faced with what he saw as an electoral imperative, believed that older people were the key to the Coalition’s re-election, and so they needed to be given more, not fewer, handouts.

In the short term, an ageing electorate with manifestly conservative views obviously helps the Coalition. Age cohorts don’t all share the same political outlook, of course: although John Howard may have been born among the people who became the flower-child generation of the sixties, it’s much more likely he was attending a meeting of the Young Fogies Society than dropping out on a hippie commune. But different age groups tend to have distinctive outlooks.

When political scientists look at the correlation between age and voting they offer two types of explanation, each with some validity. In the days when party identification was more stable than it is now, the most important effect was thought to be generational. What were the formative experiences of that age group? These days, the oldest age group voting in Australia is made up of people in the Depression generation, who experienced the traumas of the Great Depression and the second world war as they were growing up but then came to adulthood at the beginning of decades of expanding opportunities and material comforts. Members of that generation are often characterised as more security-oriented than their children and grandchildren (though that doesn’t translate directly to a more conservative voting pattern – they tend to resist the appeals of neoliberalism and deregulation, for example).

In contrast, gen Y adults grew up in an Australia that was in the midst of more than two decades of continuing economic growth. It offered far more opportunities for stimulating (if stressful and insecure) work, but also fewer prospects for accessible home ownership and affordable, high-quality childcare.

Most notably, perhaps, the electorate is becoming greener in outlook. Young adults are not only more likely to vote Green, but they also hold much stronger views about environmental issues. Within the ageing commentariat, “climate sceptics” are still overrepresented; among the newest voters, they are very much scarcer.

Political differences between age groups also arise for a second reason. As they grow older, some people become more fixed in their views; some react against the pace and scale of change; some become less tolerant towards crime, asylum seekers and other perceived threats; and some are less sensitive to emerging challenges, such as environmental issues or the problems faced by young families. On balance, these tendencies benefit the more conservative parties. Combined with the generational effect, they mean that the electoral impact of an ageing society won’t always be predictable. But we can get a sense of its impact on the 2013 federal election result by conducting an artificial but revealing experiment.

Imagine that Australia was electing two houses of parliament, each consisting of 100 members, on a national, proportional basis – one house chosen by the under-fifties, the other by the fifty-and-overs. (This is quite different, of course, from the system we use in the House of Representatives, which turns an almost permanently “hung” electorate – where no party attracts more than 50 per cent of primary votes – into a clear majority for one of the major parties.) For simplicity, the votes for the micro-parties – mainly the Palmer United Party – and for independents, which are usually clustered in local areas rather than spread nationally, have been combined as a national figure for “Other.”

Based on Newspoll data gathered just before the 2013 election, our two houses would look like this:

Older voters’ house (voters fifty years and over)

52 Liberal–National

32 Labor

7 Greens

9 Others

Younger voters’ house (voters eighteen to forty-nine years)

42 Liberal–National

36 Labor

13 Greens

9 Others

In the older people’s house, the conservatives have a slashing majority. If we assume that six of the nine Others would align themselves with the Coalition, then it would hold the house by a 58–42 margin.

In the younger people’s house, the Coalition and the six-out-of-nine Others would only have a combined forty-eight seats, and Labor and the Greens would have a bare majority. In a year when Labor and the Greens both polled badly, this contrasts strikingly with the other house. Support for the Greens was almost twice as high as in the older people’s house, and support for the Coalition parties ten percentage points lower. (This week’s Fairfax Nielsen poll found an even larger gap in support between young and older voters.)

More basic than the question of which party benefits from an ageing electorate is the impact ageing has on policy-making. As the electorate gets older, the ever-present tendency to allow immediate electoral expedience to override longer-term planning and considerations of inter-generational justice can become more pronounced. The danger is that Australian politics will be more backward- than forward-looking. Given its voter base, will Tony Abbott preside over a government by the old, for the old? •