Cost-Benefit Analysis of Seat Belts, or: The Day I Couldn’t Think of a Seat Belt Pun
St. Louis County has recently begun tightly enforcing a county ordinance allowing police to fine motorists in unincorporated areas for not wearing seat belts. So far, over 100 tickets have been given out for failing to wear a seat belt.
Once again, I think this is one of those feel-good laws that, when a layer or two is pulled back, does not make a ton of sense. Let’s take a look at this law for a moment. It penalizes any motorist who is not wearing a seat belt. Now, a seat belt is a device that protects you, and you alone, lowering the chance of injury or death in the instance of a collision. If I were driving my Danger Ranger down the road, it would make no difference to me whether every other motorist was wearing his or her seat belt. (Let’s ignore any association between not wearing a seat belt, risk-taking, and driving safely.)
Now, as with any decision, I have to consider the costs and benefits of wearing a seat belt. Some costs could be discomfort when wearing it, or the fact that my seat belt often gets caught in my car door. But these costs are offset by the benefits the seat belt offers, mainly the lower chance of injury or death that I mentioned earlier.
When talking about this law with fellow staff members here at the Show-Me Institute, a few more possible motivations for this law arose. For one, it may lead to a lower mortality rate for St. Louis County as a whole. This could be achieved in other ways, of course, such as drastically lowering speed limits, or through much stricter enforcement (as Josh Smith pointed out to me), but that would be detrimental to St. Louis County’s economy.
Here’s a fun way to look at it: The statistical value of a human life has been estimated to be $1.76 million. This figure comes from a 2002 estimate of $1.54 million, which I’ve adjusted for inflation. Now, while it can be seen as immoral to put a monetary value on human life, this number is thought to be what each person adds to society around them over the span of their life, sans all the mushy stuff like love and affection. Now, by drastically lowering the speed limit, millions of dollars would be saved in terms of human life. But the detrimental effects to our economy in terms of lost mobility and productivity would easily offset those millions. Rather, the government is able to set an equilibrium point for speed limits that is beneficial both to the economy and to human life — although the speed limit on Shrewsbury Avenue is ridiculous.
But what about seat belts? Well, it seems to me that if a person already considers the costs of wearing a seat belt to be too high, $10 will not change their mind at all. Statisitcally, it is said that you are 50 percent less likely to be hurt in an accident when wearing a seat belt. Now, the accuracy of this statistic is, of course, questionable, but shouldn’t the amount of the fine reflect it somehow? By not wearing your seat belt, you have decided that discomfort, or other costs, are a more important factor in determining your behavior than the $1.7 million you are adding to society throughout your life. But in St. Louis County, the cost for getting caught not wearing a seat belt is $10. I just wish there were more logic to this number. Sure, it’s round and ends in zero, but shouldn’t the fine at least reflect the increased risk? Why should a speeding ticket cost hundreds of dollars, and yet not wearing a seat belt only cost you 10? If you are going to make laws telling me how to drive, at least make them consistent.
Here’s a thought: How about establishing incentives to wear a seat belt (if the lower mortality or injury rates weren’t enough). Every time I drive a mile while wearing my seat belt, my insurance should drop by a penny. Sound ridiculous? It was kind of supposed to.