Here in California and across the U.S., the most common way we try to get drivers to obey traffic laws is to punish them with points on their driver's licenses. It's simple enough: Accumulate enough points and your license could be suspended, or even revoked. The idea is to give drivers a way to see how traffic and speeding offenses affect their driving privileges. Racking up points can make your insurance rates jump. Suspensions and revocations get repeat offenders off the road.
A demerit points system like ours is based on the idea that negative consequences affect behavior. That may be true, but when it comes to points on driver's licenses, it isn't that straightforward.
According to a 2010 study in the European Transport Research Review, point systems may not have any measurable impact on speeding -- but they do serve to pad insurance company balance sheets.
The study was performed on the United Arab Emirates, which passed a demerit point system for its drivers in 2008. A safety planner at the UAE's Department of Municipal Affairs and Transport initiated the study, which examined driving patterns in the city of Al Ain, which has a population of approximately 500,000.
Three months before the point system took effect and then three months afterward, researchers checked speeds on three main roads during free-flow conditions. The idea was to test the impact of the UAE's point system, in which accumulating 24 points in a year results in a license suspension and a month-long impoundment of the vehicle, with additional penalties for more.
"Spot speed data for before and after samples were divided into various classes and then the frequency distributions of these classes were compared separately for SUVs, sedans, and both types of vehicles," explained the safety planner. "The analysis revealed that the demerit points system has no significant effect on the speeding behavior of drivers."
It's not entirely clear whether the results would have been different if more tickets had been issued. It's also not clear whether the results are peculiar to the driving culture of Al Ain.
What we do know is that insurance companies have long pressed the point of view that point systems deter speeding and other traffic offenses, and that lawmakers have simply gone along. If demerit points don't have a demonstrable impact on driver behavior, are they justified?