Craig Newmark has a post about Sam Peltzman’s work on mandatory seat belt laws and moral hazard. Actually, the post is about some snarkiness between Craig and Brad DeLong, but that is not my interest. My interest is in pointing out that the seatbelt phenomenon for which Sam Peltzman is known here — that mandatory seatbelt laws can and do, at the margin, induce less careful driving than in the absence of such laws — is not just restricted to seatbelt laws. (Heck, have ya seen the way Volvo drivers drive?)
Take my favorite example, from my favorite sport: hockey. When I was a wee lassie and we had season tix to the Penguins, the players soared around the ice with their locks flowing (this was the mid-70s, after all), and there were fights, and people got injured.
Then the NHL implemented a mandatory helmet rule for all entering players; existing players were grandfathered out of having to comply. Both my casual empiricism and statistics on penalty minutes and the increase in incidence of particular penalties (especially high sticking) suggest that the Peltzman effect was in full force: mandatory helmets seem, at the margin, to have contributed to an increase in violence in hockey, particularly the nasty, cheap crap that gives hockey such a bad name.
What this moral hazard problem has provoked in the NHL is not a reconsideration of the wisdom of mandatory helmet rules, far from it. It has led to two decades of inveighing against fighting, roughing, high sticking, checking from behind, all of the behaviors that increased after the helmet rule.
Without doing a thorough (and one hopes ept, as opposed to inept, job so as not to incur Brad DeLong’s wrath) econometric analysis it’s hard to determine causality from this observation of chronology. But it is suggestive.
Years ago my husband proposed a policy that could be incentive compatible and would induce the optimal level of violence in hockey:
If you injure another player and he misses games, you must sit out the same number of games, without pay.
So what do you think? Would that do it?
Under that policy, Mr. Mid-ice-check-from-behind Scott Stevens might miss half the season (unless he changed his play), which would be fine with me. I hate seeing his vile style of play rewarded.