In the July 11th opinion piece, "Rosenstein: Should the legal BAC level be .05?", Craig Rosenstein wrote that most people only begin to be impaired to operate a motor vehicle at a BAC level of .08 and that there are no peer-reviewed studies supporting that impairment begins at lower levels. As the National Transportation Safety Board thoroughly laid out in our recent report, those statements are factually inaccurate.
Impairment begins with the first drink. As far back as 2000, a National Highway Traffic Safety Administration review of research found that drivers were impaired at BACs as low as .01. All the studies included in this literature review were peer reviewed and published in several scholarly journals. Other respected studies have found that impairment begins well below .08. By the time a person reaches .05, his crash risk is 38 percent higher than the crash risk of a sober driver.
The intent of the NTSB's recommendation is to improve transportation safety. And there's no question about it: The science and data prove that most drivers are significantly impaired by .05 BAC. And of the more than 100 countries that have already moved to a BAC threshold of .05 or lower for impaired driving, several peer-reviewed studies have shown that the reduction in the BAC led to fewer crashes, injuries and deaths.
Year in and year out, 10,000 people are killed annually in alcohol-impaired crashes. It is time for a cultural shift, from one that doesn't minimize the impairing effects of alcohol, to one committed to doing what it takes to more effectively address this ongoing national epidemic of alcohol-impaired crashes.
Deborah A.P. Hersman is Chairman of the National Transportation Safety Board in Washington, D.C.