It looks as though 16 and 17 year olds in Scotland (or at any rate some of them) will be able to vote in the Independence referendum scheduled for 2014.  And if under-18s are allowed to vote on the momentous question of whether Scotland should remain part of the UK or go it alone, it would seem strange not to allow them a voice in the composition of their local council. The former Scottish Secretary Lord Forsyth, who is firmly opposed to the suggestion, thinks it's "inconceivable" that it could just be a one-off.  Is this an idea whose time has come?

There's an attractive case in favour.  It's argued, or at least hoped, that it would increase political engagement among the young, and give an added excitement and immediacy to school civics lessons.  As things stand, turnout among 18-24 year olds is depressingly low. Extending the franchise downwards might just give young people the voting habit early.  It works for smoking, after all.  More seriously, politics has a real effect on the lives of teenagers and is vital for their future; why shouldn't they be entitled to a say in who governs you?  If you're old enough to work, pay taxes, have sex, even get married, what's so special about putting a cross on a ballot paper?

I can empathise. I remember vividly the extreme frustration, as a politically obsessed 17-year-old, of being unable to vote in a general election while people a year older who had less interest in politics got to exercise their democratic right.  It seemed unfair -- but then many things do at that age.  And I still think that many, perhaps most, people that age are quite capable of making political choices.  Walking down to a polling station is a more trivial thing than becoming sexually active, for example, yet society considers 16-year olds emotionally and intellectually capable of that.  Teenagers would naturally have different priorities from older voters, but then students have different priorities from young parents, who in turn have different priorities from pensioners, and a democratic society needs to hear many voices.

It's surely a bit optimistic, though, to imagine that handing the vote to 16- and 17-year olds would automatically inspire in them a lifelong interest in politics.  Doubtless the first batch of young voters would be briefly enthused.  But it wouldn't take long for them to discover that very little had changed, and if the voting habit can be instilled young, so can the habit of cynicism.  Especially as society would continue to make clear to people that age that, vote or no vote, they were certainly not yet adults. 

Indeed, the change would send a confusing message to teenagers.  The vote isn't just a mechanism for choosing politicians: it also has great symbolic and moral significance, as a badge of adulthood, citizenship and full participation in society, which is why the question of votes for prisoners has recently become so controversial.  For many groups in society, the vote was hard won.  Britain's electoral history is one of protracted incorporation, of a political structure maintaining itself by (often reluctantly) permitting formerly excluded groups to join in. 

When the franchise was more restricted, being of age (in those days 21) was only one of several conditions a voter had to satisfy.  Another was, of course, being male; and a further one, well into the 20th century, was owning property.  Only when women were given the right to vote on the same basis as men could they begin to take their place as full citizens.  Now that the franchise is merely a question of age and nationality, it has become, by default, a marker of adulthood.  Are 16 year-olds "adult"? In some ways, yes. The age of physical maturity has advanced in recent decades, and with it, in many cases, maturity of mind.  The Internet has brought young people (who are at home there in a way that their parents can never be) more knowledge of the world, and a greater sense of participation in it. 

But in other ways, at sixteen young people are less "adult" than they were even a generation ago.  New restrictions on the freedom and capacity of teenagers have been brought into law continually over the last decade and a half, along with a much greater sense that under 18s need society's protection, not just from sexual exploitation but also from themselves. The age at which it is legal to purchase cigarettes, knives or fireworks has been raised from 16 to 18, as has the age at which one can obtain a licence for such firearms as are still legal to possess. It's less common than it was to see a 17 year old behind the wheel of a car.  A growing number of campaigners -- ironically, many of them in Scotland -- would like to see the legal age for purchasing alcohol raised to as high as 21, as it is in the United States.  Such a move is advocated for purely paternalistic health reasons.  That with adulthood comes responsibility and freedom, including the freedom to make bad choices, is no longer an unquestioned assumption.

It's not just the law that gives 16 and 17-year-olds fewer rights and responsibilities than they used to have.  By the time they reached the original voting age of 21, many people in the past would have experienced several years effective social adulthood. Leaving school at fifteen or sixteen, they would have been working, paying taxes, and, in many cases, marrying and starting a family (and, provided it was done in that order, with less disquiet about teen pregnancy than there is today). Many boys died for their country before reaching the age at which they could vote for its government. 

The last government, by contrast, began the process of raising the legal school leaving age to 18.  A further three or four years of formal education, once rare, is becoming expected, and  as a result young people are financially dependent on their parents for far longer than ever before.   This is almost becoming a matter of policy.  David Cameron defends his latest money-saving proposal, to all but disbar under 25 year olds from receiving Housing Benefit, on the basis that they should be living at home with their parents. 

In such a context, offering 16 year olds the "adult" responsibility of voting looks patronising at best.  At worst, it looks like a devaluing of the whole idea of the vote.  As a matter of principle, excluding younger, economically active taxpayers people from the rights and responsibilities of citizenship is less defensible than excluding those who are playing much less part in adult society.  A paradox indeed. But is a vote every five years really much compensation for the loss of the independence and trust they once enjoyed? Or, to put it another way, if adolescents can be trusted with a vote, why shouldn't they be trusted with a penknife?