Following the success of her Crimes (Substituted Section 59) Amendment Act, Sue Bradford has another project: lowering the voting age to 16. This is already producing the expected sneers from Herald readers (all over 16, from the look of it), but I think its an excellent idea. To understand why, we need to delve into the basis of democracy.
Firstly, though, we need to deal with an obvious canard. Contrary to the claims of conservatives who talk grandly of "the public interest" (which somehow always coincides with the interests of the rich), democracy is not about making good decisions. What constitutes a "good" decision depends very much on what your goals and interests are, and its clear that there's no broad agreement on that. Instead, it is a system for making our decisions - decisions we as a society can own. It is not a system for aggregating information and reaching a rational decision about what we should do - it is a system for moderating conflicting interests without the need for a messy civil war.
The moral basis of this system rests on two assumptions: firstly, that people have interests, and secondly, that no-one's interests count for more than anybody else's. The first is simply a recognition of fact. The second is a statement of fundamental moral equality, and can be taken as axiomatic or justified on the basis of consistency (if I want my interests to count, then I must agree that everyone else's do as well). Note that there's nothing in here about rationality, or about age - if you have interests, you should count.
In practice, all states have adopted arbitrary age limits on the franchise. However, the moral egalitarian basis of democracy has produced an unrelenting downward pressure on those limits, which has seen them fall from a generally accepted age of 21 to the now generally accepted standard of 18. And the pressure is still there. As education systems improve, and the young become more independent, then the age should be lowered.
(I should add at this stage that the inability of modern democratic systems to properly represent the interests of children and young people is a well-known flaw. Because they cannot vote, they have no effective voice, and it is particularly easy for their elders to pursue policies which unfairly impose costs on them. Running deficits, using finite resources, and allowing pollution are three general examples. More specifically, there's the American policy of conscription during the Vietnam War (which targetted people who could not then vote), and New Zealand's own student loan scheme, which imposed costs on future tertiary students so that their parents could enjoy lower taxes. A lower voting age will make these sorts of abuses more difficult).
New Zealand has traditionally taken an expansive attitude towards the franchise. We were one of the earliest countries to abolish property qualifications for voting, and the first country in the world to have full universal suffrage. We extend full voting rights to residents, on the basis that they too have a stake in our society. And I think the time has come to extend it to young people as well. 16 year olds have interests, and those interests should be counted.