Putting age restrictions on certain things like buying alcohol, driving a car or voting in elections can seem arbitrary, even random. How does a government decide when people are ready?
As a 16 year-old living in Aotearoa in 1881, you could head down to the pub after school, if you so chose.
There was no law against it - the drinking age in on-licenses was 16 back then.
As for the purchase age in off-licenses, well, there wasn't one. If your dad was a bit tired after work and had a particularly precocious three year-old, he could send them down to the liquor store for a gallon of mead, or whatever was your drink of choice.
A few years later, in 1910, things changed. The drinking age was raised to 21 for on-licenses. Off-licenses followed in 1914.
In 1969, both were lowered to 20.
Then, in 1990, 18-year-olds were allowed to drink in bars - and nearly a decade later, in 1999, the off-licence age also dropped to 18. It's remained there ever since.
All of which is to demonstrate that age limits on rights and privileges are dynamic. They change over time.
We do this for lots of stuff. Booze, cigarettes, gambling, criminal responsibility, adoption, standing for public office and, of course, voting.
But every now and then, the winds of change pick up. And picking up they are.
Earlier this week, the Supreme Court issued a ruling pertaining to the voting age, which is currently 18 for both local body and general elections.
People over the age of 16 are protected against discrimination on the basis of age under the Bill of Rights Act, unless this discrimination can be justified.
A lobby group, Make It 16, felt the age discrimination in this case - limiting voting rights to over-18s - was not justified, and asked the Supreme Court to issue a declaration of inconsistency.
The court did: it agreed with Make It 16, saying the Crown, through the attorney-general, had failed to even try to justify the age discrimination at play here.
"This is what the court says," says Auckland University law associate professor John Ip.
"The attorney-general has to show why 18 was chosen as opposed to 16 or 17, given the prohibition on discrimination expressly defines the scope of protection at age 16.
"And then the court says: the attorney-general is candid that he has not sought to do that. Which is like saying, you know what, I'm just not gonna play."
Now, this is not the court saying 16 and 17 year-olds do have the right to vote. It's simply the court saying there is an inconsistency in the law, and telling the government to consider doing something about it.
The actual mechanisms to get the voting age lowered are more complicated and, to be honest, less likely to succeed.
A parliamentary super-majority would be required - at least 75 percent, requiring cross-party support, which seems unlikely.
Alternatively, a referendum would be required - and public sentiment very much seems against the idea.
However, changing the voting age in local body elections - as has happened in Scotland, for example - would be a much simpler exercise, requiring only a simply majority of 50 percent of MPs.
In the end, different people will have different views on this.
Take The Detail's Emile Donovan - he told Massey University's Richard Shaw that his personal view was that 18 felt about right when it came to voting, but that he would struggle to formulate a convincing argument, saying it was more down to 'the vibe' of it.
Shaw sympathises with that somewhat spurious justification, but feels it misses some notable societal changes.
"When we use that term, 'vibe', we're trying to capture...things that are hard to pin down.
"[But] we know that even though the proportion of people aged 18-to-24 who are enrolling and turning out to vote is a little bit higher now than it was two or three elections ago, it's still substantially lower than is the case for most - all - other age cohorts.
"We know voting is habit-forming...and the reverse also applies.
"There is a train coming down the line in 30 or 40 years' time: if we don't involve in greater numbers in formal, arena, institutional politics, we're going to have a really hollowed-out system.
"One other thing about the 'vibe': Bill Rowling had a vibe. In 1974 when he was prime minister, and the third Labour government was putting through legislation which would drop the voting age from 20 to 18, Bill Rowling made a really interesting speech in the House.
"Rather than framing the right to vote as a right, he framed it as a responsibility. And he wasn't alone: members of the National Party opposition were saying look, it's a responsibility, young people need to be brought into the nation of which they are citizens, and they need to accept their responsibility, their civic responsibility as citizens.
"I look at the enrolment trends, the turnout trends, I look at the state of the world, and I think, I would quite like to have more of those young people accepting a civic responsibility, to enter into the public domain, and engage with it through the voting process.
"I feel we would all be better off for that."
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