Drunk driving prevention is difficult, but we already know how to do it

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:

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.

According to this study by the National Highway Traffic Safety Administration, the risk of a crash is 1.74-2.69 times higher at a BAC of 0.08. At 0.15, crash risk is increased by 8 to 22 times, and at 0.20 the risk is 21 to 82 times higher relative to driving unimpaired. (The ranges represent the difference between the study's observed crash rates and its adjustment for those who refused to participate, were involved in hit-and-runs, etc., so the higher number is theoretically the more accurate risk estimate.) So in Washington, even though you're about 30 times more likely to get into a wreck at a BAC of 0.20 compared to 0.08, the punishment hardly differs at all. In the eyes of the law, the severity of each crime is essentially the same. Below is a graph from the study, illustrating the exponential increase in crash risk as BAC increases:

Crash risk vs. BAC, from NHTSA.

DUI laws in Washington (and many other states, I'm sure) aren't very sensible, but we can look elsewhere for guidance toward a better system. Although I think it still underrates the seriousness of BAC levels much higher than 0.08, Wisconsin has a system that's definitely superior to Washington's. There, penalties double, triple, and finally quadruple as BAC increases. A driver with a >0.25 blood-alcohol content faces penalties four times greater than someone arrested for DUI with a BAC between 0.08 and 0.149, and this includes fines, jail time, and license suspension. Of course, we can see from the above graph that a person with a BAC of 0.25 has a 160-times higher risk of getting into a collision compared to a sober person, and fifty times the risk of a person with a BAC of 0.08, so penalties that are only four times worse (at most) don't really capture the seriousness of driving with a very high BAC.

If BAC-scaled penalties aren't the solution, what is?

Based on the data from Wisconsin, increasing penalties for more serious drunk-driving infractions is not the whole solution. That doesn't mean it can't be a part of it, but it's not enough by itself. So what else can we do? My next thought was that perhaps part of the problem is that, at least in Washington, we so rarely actually convict people of DUIs. I have several friends who have been arrested for DUIs, and all of them were able to plead down to a "wet reckless" with the help of a lawyer, a much less serious crime, even though they blew over a 0.08 on the breathalyzer. Maybe the problem isn't that DUI penalties are insufficient, but that so few people are actually convicted of the crime they've committed.

Nope. Texas doesn't allow defendants to have their charge reduced to a wet reckless, and yet they had even higher rates of alcohol-related fatalities than Wisconsin did. Again though, things aren't so simple: Texas has extremely lax penalties even for a DUI conviction, with no minimum for fines, and as little as 3 days in jail and a 90-day license suspension.

Like I said, this turned out to be pretty complicated (again--surprise!). The most effective solution I found was actually a program that started in Washington state itself in November 2006, and was followed up in 2010. The study was performed in the three biggest counties in Washington and consisted of adding six--yes, just six--state patrol officers to each county, their primary goal being to crack down on alcohol and drug-impaired drivers. The report can be found at the NHTSA's web site [PDF]; it's only 5 pages and I encourage you to check it out for yourself. The gist of the report is captured by the following graph:

From National Highway Traffic Safety Administration.

The TZTP counties are the three with the extra WSP officers. As you can see, compared to the average over the previous five years, the TZTP counties experienced a 34.4% decline in alcohol- and drug-related fatalities. That's in one year. Compare this to a 28.4% increase in the next two biggest counties (Clark and Spokane), and an 8.5% decline in the rest of the state. It's very possible that the numbers might jump up a bit after people get used to the presence of these extra patrols, but the difference between the pre- and post-TZTP eras is stark and worth investigating further. I have to reiterate once more that this is the result of adding just 18 officers (plus another ten or so support staff) to three counties with a total population of 3.5 million. We could do much more.

During the 10-month window of the study these officers made over 3,000 DUI arrests, 3,000 speeding citations, and 900 seat belt citations. In theory this should mean several million dollars in fines, more than enough to cover the expense of these extra patrols. Due to the leniency of our sentencing, however, I couldn't really guess what we're actually collecting as a result of these arrests. But more importantly than all that, the presence of these officers saved dozens of lives, possibly including the innocent drivers, bicyclists, and pedestrians these drunk drivers might have struck with their vehicles. The fact that it was at essentially zero cost to the state is just icing on the cake.

One way to ensure that we can capture that revenue and keep our drunk-driving patrols funded is to follow in Texas' footsteps (never thought I'd say that) and stop allowing offenders to plea down to wet reckless. Instead of punishing drunk drivers through the justice system's fines and suspensions, we're basically just redirecting that money to DUI lawyers--the people I know that were arrested for DUIs each paid about $5,000 through the whole process, but most of that money went to their lawyers. And for what? What do the lawyers contribute? No one is disputing the fact that these people were driving with a BAC at or above 0.08. The state should collect that money itself in the form of the DUI fines it rarely seems to collect, and use it to fund more patrols instead of enriching a few unnecessary lawyers.

I started this post planning to make a strong argument for increasing drunk-driving penalties, but after starting to write I realized there isn't evidence to back up my claims. Not without controls that don't yet exist, at least. And that's fine. Perhaps not surprisingly, I learned that enforcement seems to be the most effective way to prevent drunk driving and save peoples' lives. These two arguments intersect, however, at funding. If we want to be able to pay for extra patrols, the money needs to come from somewhere, and more strict penalties--or consistent sentencing, at least--could be part of the solution. And as we work to increase enforcement and seek to provide further evidence for its efficacy, let's keep finding new ways to prevent drunk driving, whether that means harsher penalties, more accessible alcohol and drug treatment programs, better transportation options, or all of the above. Even the most incremental improvement can mean hundreds of lives saved over the next few decades, and safer roads for everyone.

In Washington state, the gas tax is not a user fee

Over the 2011-2013 biennium Washington state is projected to collect about $2.5 billion in gas tax revenue, or roughly $1.25 billion per year. The state gas tax rate is 37.5 cents per gallon, which means we used 3.3 billion gallons of gasoline last year. For none of that gasoline were drivers required to pay sales tax, depriving the state of more than $800 million in revenue. Why don't we pay sales tax for gasoline in Washington?

The simplest answer is that sales tax has been replaced by the gas tax for this specific consumer good. The state began imposing a gas tax in 1921, starting at one cent per gallon. At the time gasoline cost about 26 cents per gallon. (This pdf has a list of all the Washington state gas tax levels since 1921, and this one has the average national gas price since 1919.) When the State Constitution's 18th amendment passed in 1944, the state gas tax was at 5 cents per gallon. The 18th amendment says the following (paraphrased by the Department of Transportation):

The 18th amendment to the Washington State Constitution dedicates motor fuel tax collections to “highway purposes". Revenue generated from the gas tax is distributed to counties, cities and state accounts. The state receives about half of the total revenues collected. These are the funds which support the WSDOT highway programs as well as the Washington State Ferry System, which is deemed a state highway system by constitution. Highway construction, maintenance, preservation, administration and debt service on highway construction bonds are all funded by these revenues. The other half of the fuel tax revenues are distributed directly to cities, counties and other agencies for roadway programs that are not part of the state highway system.

This means that all gas tax money must be spent on roads, although there is some flex to whether this applies to certain transit programs. At the very least, all of the money must be used for transportation purposes, and certainly the vast majority of transportation dollars are spent on  roadways. In this biennium, for example, the WSDOT's budget is $7 billion, four billion of which is devoted "highway improvements," with another $750 million for "highway preservation." (Less than 10% goes to rail and transit.) Over this two year period, the gas tax barely covers half the cost of highway construction and repair. Worse, this is true despite the fact that we fall further behind on road maintenance every year.

Many drivers feel they "pay their own way" for the infrastructure they use in the form of various taxes, fees, and tolls, but can this really be true when they're exempted from paying normal taxes on the purchase of gasoline? After all, if I buy a new couch at a furniture store, the tax I pay is not earmarked to help me pay for a place to store it. Sales tax paid for a new ink cartridge in my printer isn't earmarked to compensate me for said printer. Perhaps most tellingly, when I buy a bicycle the sales tax on it isn't dedicated to new bike lanes, cycle tracks, pothole repair, or anything else meant to help me get around safely and efficiently. And it probably shouldn't, because it would be extremely limiting to government's ability to decide where the greatest need is, and where the tax proceeds of my purchase should be spent.

As long as gas is exempt from sales tax, drivers can't claim that the gas tax is a "user fee" anymore than the tax I pay on a Subway sandwich is a "user fee." Compare to a true user fee, the tolled road: roads and bridges tend to be free to drive on, but a toll has been added in order to help pay for construction and/or maintenance of the road. A gas tax, on the other hand is not an additional charge placed on top of the cost of driving. Instead, it's a bait-and-switch in which money is effectively taken from the general fund (via lost sales tax revenue) and moved into the motor vehicle fund every time someone purchases gas. This is particularly true now, when, at current gas prices, sales tax or fuel taxes would produce almost exactly the same amount of revenue for the state.

Worse, calling it a "gas tax" gives some drivers the fantasy that they're paying their own way without assistance, when in fact the cost of building and maintaining our road infrastructure falls on everyone. Even if the gas tax actually was a user fee, it wouldn't come close to funding our highway program--even with the addition of vehicle- and driver-related fees--and would need to take money from the general fund (as it does now). And this is fine! Infrastructure is important and should be funded adequately, but when we give certain groups of people the impression that they're the "producers" and everyone else are the "moochers," we end up making infrastructure decisions that aren't in the interest of the cities, the state, or our future, and having unproductive fights about how bicyclists, pedestrians, and transit users are "stealing" money from drivers. 

Likewise, although I don't own a car I still make use of the roads. I take the bus, ride my bicycle, walk, and occasionally get rides from friends or family for more distant events. I'm glad the roads are there (many of them, at least), and happy to pay for my share of them. But with driving on the decline and driverless cars likely to reduce congestion in the future, building more roads is a strategy that favors current drivers at the expense of current non-drivers and the future generations that are forced to maintain or demolish their excess capacity. This isn't intended as a demonization of drivers, it's simply a recognition that they don't warrant any special status, including a sales tax exemption for the product that makes their vehicles run.

A better system would be to stop exempting drivers from sales taxes and devote 100% of gas tax revenues and user fees to maintenance and existing bond repayment. This would have a few key benefits:

1. State revenue would increase by about $1 billion per year, and could be spent on education, health services, public safety, or whatever's needed, including transportation;
2. We'd be performing some minimum level of road maintenance that is clearly not being met currently, and tends not to be considered in the total cost of road construction;
3. We'd be less likely to continue accumulating infrastructure that isn't going to be useful in the future;
4. The remaining transportation budget could be spent rationally, since none of it was coming exclusively from drivers or devoted exclusively to them; and
5. Consumption of gasoline would be discouraged further.

Then, of course, there are downstream benefits of this, like better transit service, less pollution and congestion, healthier people, and all the other things that come with less auto-oriented places and more spending on social services. 

Now, reinstating the sales tax is probably something that couldn't happen without a repeal of the 18th amendment which, unfortunately, seems very unlikely. But it doesn't mean we should just accept this destructive and misleading status quo, either. Even without removing gasoline's sales tax exemption we could dedicate all gas tax revenue to maintenance, for example. We could still raise the fuel tax, which historically has been closer to 20% of the cost of gasoline, rather than the current ~10%. And most importantly we can make it clear that everyone helps pay for transportation infrastructure, and all of our voices matter in the decision-making process--including those who are going to have to live with (and pay for) the consequences in years to come. Compared to everyone else, those who drive the most don't contribute more to the state's budget--they just contribute in a different form--and they shouldn't receive any special subsidies or elevated stature because of it.