A very good paper from a few years ago landed a punch to the public health argument for smoking bans by showing that they increase drunk driving. A paper in the new AEA Applied Economics Journal provides the knockout blow with evidence of another, arguably worse, health externality caused by smoking bans. They argue that laws that ban smoking in bars and restaurants do not actually decrease the amount of secondhand smoking that people are exposed to, just the distribution of who gets exposed.

It turns out that bans don’t cause people to decrease the amount that they smoke, but rather where and when they smoke:

…we find that a total ban decreases the time spent by smokers in bars and restaurants by about 20 minutes per day. Moreover, as implied by the model presented in Section I, we observe an increase in the amount of time that smokers spend at home when a smoking ban in bars is introduced (on average smokers spend 57 more minutes at home).

The authors measure the effect these laws have on exposure of non-smokers to secondhand smoke using a dataset of individuals level of cotanine, which is a chemical that stays in the body over 20 hours after exposure to nicotine. They find that these bans increase the exposure for children who live with smokers by an equivalent of two to four cigarettes per day. As a result of these laws people are staying home more and smoking just as much as they normally do, thereby exposing their children to more secondhand smoke.

I personally enjoy smoking bans. It makes my life more pleasurable, and it seems to me that most people I know agree, even a lot of the smokers. I can imagine that some smokers, especially casual smokers, prefer to be constrained so they aren’t as likely to smoke when they go out. But what level of unintended consequences are we willing to tolerate here? First the previous research showed that smoking bans raise the risk for people to be killed by drunk drivers, and now this new research shows that it increases children’s exposure to secondhand smoke. Meanwhile, the people being made safer are those who can choose whether or not to expose themselves to the smoke: employees and patrons of those bars and restaurants. This seems extremely perverse to me.