Drunk driving prevention is difficult, but we already know what it takes

Out of roughly 34,000 traffic-related fatalities in 2009, about one-third involved a driver with a blood-alcohol content of 0.08 or above (the minimum for a DUI offense in every state). Thinking about this I wondered whether this number could be reduced by increasing the penalties for higher BAC levels, since the chances of a collision rise quickly as impairment increases, but fines, suspensions, and jail time do not. After doing some research on the subject, I found instead that this is actually a very complicated issue (surprise!), and my intuition didn’t really stand up to scrutiny. Case in point was Wisconsin, a state that already has penalties that scale with BAC but in both 2008 and 2009 had significantly higher rates of alcohol-related fatalities than the national average. Something else is going on here.

Just so you can get a sense for the argument I was making originally, here’s the bulk of what I’d written before deciding to add the above disclaimer and what comes afterward:

First idea: drunk driving penalties should be more closely tied to blood-alcohol content

The penalties for a DUI conviction usually include a small amount of jail time, a 30-day to one-year driver’s license suspension, and a few hundred to a few thousand dollars in fines–most states also have enhanced penalties which kick in BAC levels of 0.15-0.20. In the case of Washington state, though, the increased penalties for BAC at or above 0.15 don’t have much bite: the same maximums for jail time and fines, with barely increased minimums, and a longer license suspension, one year instead of 30 days. Drunk driving of any kind is a serious crime that threatens the lives of the driver, passengers, and anyone else on the streets or sidewalks, but there’s a big difference between driving with a 0.08 and a 0.15 BAC. We need to formally recognize this reality, and ensure that the penalty is commensurate with that increased risk.