This election day, more than 8 million Americans who are perfectly capable of making informed and reasoned political decisions will be denied the privilege of voting. I'm talking about 16- and 17-year-olds.
Over the last 40 years, there has been occasional discussion in the United States about lowering the voting age, an idea that has been gaining popularity around the world. In parts of Europe and much of South America the voting age is 16 or 17. The United Kingdom is debating allowing 16-year-olds to vote, and the discussion has picked up steam following Scotland's recent referendum on independence, in which those 16 and older were permitted to vote — and did so in great numbers. Studies of elections in countries that permit 16-year-olds to vote on state and local matters find high turnout in this age group as well.
Societies have long grappled with where to draw the legal boundary between adolescence and adulthood; today nearly all countries use 18 as the age of majority. The United States stands apart from most of the world in that it uses different ages for different rights and responsibilities. We permit people to drive when they are 16 (even younger in a few states), but prohibit them from purchasing alcohol until they are 21. The ages at which adolescents can see a sexy movie, marry, enter into contracts, or buy cigarettes fall between these two extremes.
Each approach — using a single age for all legal boundary-drawing or deciding each issue on a case by case basis — has merits and drawbacks. The one-age-fits-all regime has the advantages of consistency, clarity and fairness. Once you're an adult, you're an adult. If you're old enough to work, pay taxes and serve in the military, you ought to be old enough to drink, smoke, drive and vote.
The issue-specific approach is potentially wiser because it permits society to align legal responsibilities and privileges with people's abilities and needs. However, in practice we create legal boundaries for a complex mix of political and practical reasons, which frequently lead to laws that make little sense. Surely no one thinks it's easier to handle a car than a beer. But some 16-year-olds need to drive because public transportation is limited in most parts of the country, and the drinking age is 21 in part because we worry about young people drinking and driving. (Actually, countries with a higher driving age but a lower drinking age have far safer highways than we do.)
If we used the science of adolescent development to guide our thinking about the age of majority, we might reach different conclusions about when to extend adult privileges to young people. The voting age is a case in point.
Science does not point to an obvious chronological age at which a bright-line legal boundary between adolescents and adults should be drawn for all purposes, but it is instructive. Most aspects of emotional and intellectual maturity reach adult levels sometime between 15 and 22. Adolescents' judgment in situations that permit measured decision-making and consultation with others — what psychologists call "cold cognition" — is just as mature as that of adults by 16. In contrast, adolescents' judgment in situations that evoke "hot cognition" — situations in which their emotions are aroused, time pressure is a factor and they are in groups — is not fully mature until they are older, certainly no earlier than 18 and maybe as late as 21.
If science were an important consideration in setting the age of majority — as I think it should be — a reasonable starting point would be to distinguish between two sets of laws: those for activities that involve cold cognition and those for ones involving hot cognition. Cold cognition is relevant to matters such as voting or granting informed consent for medical procedures, for example. Adolescents can gather evidence, consult with others and take time before making a decision. Adolescents may make bad choices, but statistically speaking, they won't make them any more often than adults.
A later age of majority is more sensible for matters that involve hot cognition, such as driving, drinking and criminal responsibility. Here the circumstances are usually those that bring out the worst in adolescents' judgment — they frequently pit the temptation of immediate rewards against the prudent consideration of long-term costs, and occur when people are emotionally aroused, and are influenced by their peers. For these sorts of matters, the age of legal adulthood ought to be 18.
The last time we lowered the voting age in the United States was 1971. We've learned a lot about adolescence since then — enough that we should now lower the voting age to 16.
Laurence Steinberg is professor of psychology at Temple University and the author of "Age of Opportunity: Lessons From the New Science of Adolescence."