Friday, May 31, 2013

Op-Ed: Lower that Legal Limit!

Every day, in the United States, one person dies every 48 minutes in a motor vehicle crash that involves an alcohol-impaired driver. These tragic crashes cost the United States more than 51 billion dollars each year (1). Given these stark and grave statistics, I urge the federal government to lower to legal alcohol limit for non-commercial drivers in the United States. 

Alcohol-impaired deaths account for nearly one-third
of all crash deaths. Source: CDC (1)
The “legal limit” refers to a driver’s blood alcohol concentration (BAC), or the percentage of alcohol in the blood by weight (2). Currently, all 50 states within the US subscribe to 0.08 BAC as the legal limit for non-commercial drivers. Historically speaking, the legal BAC used to be set at 0.10 in some states (3). The inconsistencies that come with letting states set their own legal levels of BAC for drivers is why this change needs to occur on the national level.

Many other countries around the world have set their legal BAC at 0.05, with several countries imposing an even stricter limit (2). I am recommending the 0.05 BAC limit for the sake of political feasibility, given our individualistic and rights-based society.  Starting out with this small reduction in the legal alcohol limit for drivers will help show citizens the benefits of this change, setting up the potential for an additional reduction in the future.

The tendency of many Americans to act in an individualistic, “don’t tread on me” manner will be one of the biggest barriers to this proposed change. A common argument against reducing the legal BAC for drivers is that it does nothing to deter the “heavy drinkers,” who are assumed to be responsible for causing collisions that result in property damage, injury, and even death.

Contrary to this belief, “heavy drinkers” are not always the ones behind these collisions. Many surveys and studies show that light to moderate, or “social,” drinkers report getting behind the wheel after having too much to drink. In fact, “each year, roughly 4 million people admit to driving while under the influence of alcohol” (3). To assume that all four million of these people are “heavy drinkers” is certainly a stretch.

Reaching a certain BAC level depends on several factors, including weight, gender, number of drinks, speed of drinking, tolerance and the amount of food in your stomach (5). The proposed 0.05 BAC level typically requires the consumption of just over 4 drinks in 1 hour for a 180-pound male, and 2 drinks in 1 hour for a 130-pound female (3). Many individuals do not realize that a “drink” in BAC level terms is 12 ounces of beer, 5 ounces of wine, or 1.5 ounces of hard alcohol (5). Keeping these official measurements in mind can become especially difficult in a social setting, such as a happy hour.

Reducing the legal BAC has many implications, including great benefits for perceived and actual safety. Impairments that affect driving ability occur much earlier on the BAC spectrum than many people assume.
Similar to other findings, the National Transportation Safety Board (NTSB) reports that, at 0.05 BAC, “some drivers begin having difficulties with depth perception and other visual functions. At 0.07, cognitive abilities become impaired,” which is when dangerous situations tend to arise (3). Keep in mind that we haven’t even reached the current legal level!

The NTSB wholly supports this recommendation (3). As stated in an article on NBC News, roughly “10,000 people die in alcohol-related traffic [collisions each year,] and 170,000 [people] are injured” (3). These numbers are certainly an improvement from the 20,000 people who died in this type of collision 30 years ago, but the threat to public safety is still very real. As a driver, the risk of getting in a collision, compared to driving sober, jumps from a 39 percent increase at a 0.05 BAC level to more than 100 percent increase at a 0.08 BAC level. These odds would be great for something like a poker game, but are instead very startling and frightening when you consider how many people self-report driving under the influence.

When Australia reduced their legal BAC from 0.08 to 0.05, the country saw between a 5-18 percent drop in fatalities. When Europe made the same change, they saw their fatality rate cut in half (3). If we saw a similar outcome in the United States, we would save between 500 and 5000 lives each year! The NTSB conservatively estimates that at least 800 lives could be saved each year (3). On top of this significant benefit, we would also save a great deal of money in medical, court, and traffic-related costs. More than 100 countries worldwide have adopted this lower 0.05 BAC limit, including Denmark, the Philippines, and Switzerland (3, 4).

While factors such as street design, traffic calming, and urban form all have impacts on safety, I do not believe that these efforts go far enough in reducing the incidence of driving under the influence of alcohol. By lowering the legal limit to 0.05 BAC, drivers are deterred from drinking and getting behind the wheel, given the narrower threshold of acceptable BAC. The threat of getting caught increases, and the costs (causing a collision, getting arrested, and paying fines, to name a few) start to strongly outweigh the perceived “benefits” of driving while under the influence. A concurrent educational campaign would lead to increased public awareness and subsequent social stigmatization of driving under the influence. This chain of effects would greatly assist in this recommendation’s success at reducing the number of inebriated drivers on the road, endangering the safety of countless innocent people.



  1. I think your post draws attention to a very serious issue. I have noticed within the past year or so a few billboards around town stating "Buzzed Driving is Drunk Driving". I think this is a good way of educating people on drinking and driving.

    I think lowering the alcohol limit could be beneficial, but maybe going a step further and providing breathalyzers at places that sell alcohol or backing a proven and reliable breathalyzer that individuals can carry with them.

    I recently have seen a few breathalyzers on the market that plug into a users smart phone. Perhaps making breathalyzers more available, socially accepted, reliable, convenient, and affordable could have an even greater impact.

  2. Great post Kelly, I had many doubts at the beginning but you addressed nearly every one of them by the end - a sign of a very convincing op-ed.

    The one thing that I was left wondering about is how many crashes currently involve drivers in that 0.05-0.08 range. The other countries experience indicates that it could be substantial, but I would think that's not really data that gets collected presently.

    I also agree with Shawn that more widespread breathalyzer access could be a great way to connect with drivers. Even with drink-weight-time charts and such, it seems there's a pretty large disconnect between would-be drivers perceptions of BAC and reality.

  3. Shawn & Ben- thanks for the comments! I too think that the breathalyzer idea is interesting, but wanted to stick to one topic for the sake of the op-ed. In my research, I found that the CDC advocates for sobriety checkpoints, which reduce alcohol impaired driving by 9%, and ignition locks in cars driven by people with a criminal record of driving while impaired. The CDC associates the latter strategy with a 70% reduction in arrest rates! Very interesting possibilities.

    Ben, to answer your question about crashes in the 0.05-0.08 range, I estimate around 1400 (out of a little over 12,000 fatal collisions in 2009), based on a bar graph you can look at here:

    That same pdf from the National Highway Traffic Safety Administration also states that 84% of total alcohol-impaired fatal crashes involved drivers with BAC levels above 0.08; 56% had BAC levels at or above 0.15! This data only focuses on fatal crashes; I didn't come across the same numbers on general alcohol-impaired crashes.

    Thanks again for the comments and questions!

  4. In addition to or even instead of lowering the limit, I believe we should have far stricter punishments for drunk driving. Not only stricter punishments but more importantly stricter enforcement. Let's say you lost your license for one whole year as a first offender, jail time for the second, etc. I read up on some of the strictest drunk driving punishments around the world which mainly focused on fatal crashes (80 lashes in United Emirates, 4 year Siberian prison in Russia) but this one exemplifies my point:

    "An Ohio judge in 2007 sentenced Jess R. Brown to 16 1/2 years in prison after he pleaded guilty to his 19th and 20th DUI offences, the maximum allowed by state law. The judge said it was the worst DUI record she'd ever seen."

    Why did that guy have to get caught 18 other times before serious measures were taken? Do you think that having their license revoked for a year, or 1000 hours of community service, or 1 year in jail for first time offense would discourage people from trying it out?


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