Do seatbelts save lives?

john nash

Mathematician John Nash on whose life the movie A Beautiful Mind is based, was recently killed in a car crash. Nash and his wife Alicia were sitting in the back seat of a cab and were not wearing seatbelts. The couple were ejected from the car when it crashed into a guard rail.
The driver of the car escaped death because he was wearing a seatbelt. Chances are that the Nash couple would have survived the crash as well if they had been wearing seatbelts.
Nevertheless, the question to ask here is do seatbelts really save lives? It needs to be borne in mind here that I am not just talking about the individuals in the car, but also about those who are walking on the road.
As Steven E. Landsberg writes in
The Armchair Economist—Economics and Everyday Life: “Back when seat belts (or air bags or antilock brakes) were first introduced, any economist could have predicted one of the consequences: The number of car accidents increased. That’s because the threat of being killed in an accident is a powerful incentive to drive carefully.”
What Landsberg meant here was that drivers drive less carefully once they know that their cars are safer. If the cars are less safer, then there is an incentive for drivers to drive more carefully, else they are likely to end up dead or be seriously injured. With a seatbelt, the chances of surviving an accident go up and this leads to drivers driving less carefully. And this makes their cars more dangerous for the people walking on the roads.
In fact, Landsberg jocularly told me in an interview I did with him a few years back, that: “If I took the seat belts out of your car, wouldn’t you be more cautious when driving? What if I took the doors off? So if we really wanted to reduce the number of driver deaths, the best policy might be to require every new car to come equipped with a spear, mounted on the steering wheel and pointed directly at the driver’s heart. I predict we’d see a lot less tailgating.”
In fact, John Adams, an emeritus professor at University College London has carried out research in this area. His findings suggest that making the use of seatbelts compulsory in 18 countries either led to no change or an increase in road accident deaths.
What is interesting nonetheless is that wearing seat belts leads to a reduction in the number of driver deaths. Nevertheless, because the drivers feel safer with the seatbelts on, they are likely to drive more recklessly. And this leads to an increase in overall road accident deaths because the number of pedestrian deaths tends to go up.
Also, seatbelts do not save many driver lives either. At least, that is what research carried out by Professor Dinesh Mohan of IIT Delhi suggests. As he writes in a research paper titled
Seat Belt Law and Road Traffic Injuries in Delhi, India : “An estimated 11-15 lives may have been saved in Delhi per year due to current levels of seat belt use out of a total of 1,800-2,000 fatalities per year on Delhi roads. This amounts to less than 1% reduction in total fatalities due to road traffic crashes in Delhi because a vast majority of crashes comprise vulnerable road users and motorised two-wheeler riders.” Given that Mohan’s paper was published in 2009, this finding is a little dated though.
To conclude, what all this tells us is that “people respond to incentives,” which is the fundamental principle of economics and as Landsberg writes: “when the price of accidents(e.g., the probability of being killed or the expected medical bill) is low, people choose to have more accidents.” And that is something worth thinking about.

(Vivek Kaul is the author of the Easy Money trilogy. He can be reached at [email protected])

The column originally appeared on Bangalore Mirror on June 3, 2015