Drinking age as a factor in the Increasing Age of First Marriage

For a while, since the heady days of the feminist ’60s, the age of first marriage has been increasing at a steady pace.

The median marriage age in America trends look like this:

Various reasons for this have been documented elsewhere and include the increasing acceptance of inclusion of women in the workforce, birth control, urbanization trends and the effects of communications and transportation innovation, the collapse of the nuclear family (chicken-and-egg problem, there), education trends, etc.

I would like to add one more to that pile of weighty Ph.D thesis-hypotheses: the establishment of a national legal drinking age in 1984. The national drinking law creates an artificial social barrier to proximity by increasing the costs associated with prime marriage-age people mingling socially.

Among other things, attraction is determined heavily by proximity.  This means that people who are together are more likely to pair off. Hence the heavy number of couples that come from proximate environments like work, school, etc, but random pairings (e.g. you meet someone on the subway) are comparatively much more rare.

What determines proximity? Well, there are the aforementioned environments where people spend a lot of time around the opposite sex. However, there’s also the classic recreational and social activity of going out with friends. This often takes place at bars or restaurants where drinking takes place. If a sizable portion of the marriageable population is excluded from that environment (i.e. carded), then they can’t be proximate to those who can do it.

Therefore, they are unlikely–by virtue of lack of proximity–to be attracted and get married.

The chart above bears this out (sort of). For much of the 1900s, until about the mid-1970s, the marriage age for women was at 21 or below. This, being a median figure, indicates that many women getting married were below 21. So at least half of the women on college campuses (a better estimate might be 70%) couldn’t drink legally. Most of the guys married, on the other hand, were at a median age of 23. This means that the women getting married were put into in a different legal state of eligibility  for common social activities than the guys who were getting married.

Well, guess what? After the minimum drinking age law was passed, recreational social activities with one’s friends (e.g. going for dinner, going to a bar, going to the bowling alley, etc) just had a lot more friction associated with them–I might be arrested for buying alcohol for a minor if I’m a college senior and my girlfriend is a junior or sophomore and I buy her a glass of wine at a bar. If I can’t bring my girlfriend out with my friends, I’m less likely to hang out with her. This means less proximity, and less attraction, and less marriage until later.

You might argue that alcohol isn’t everything to a relationship, and you’d be right. There are undoubtedly many, many other more causative factors in the increase of marriage age. But it’s not surprising to see the median ages of marriage increase to the point where socializing with marriage prospects isn’t likely to get you in jail for providing alcohol to a minor.

You might also say that most of the increase in marriage age happened before and continued happening after the law, and again, you’re right. But you’d be hard-pressed to say that this definitely isn’t a factor, given the age differential of marriageable men and women and the barriers to interaction (i.e. incentives) that it puts in place.

This is an example of how well-intentioned policy can have unintended, unanticipated, and sometimes un-noticed effects well beyond what was meant for the law to achieve, whether or not you think it’s a good thing.