Since being created in 1967, originally as part of the Department of Transportation (since 1975, it’s been a five-member independent agency), the National Traffic Safety Board (NTSB) has performed many useful functions. First and foremost, it investigates major accidents involving the nation’s roads, rails, airways, waterways, and pipelines. The agency also conducts studies on safety issues and recommends ways to improve safety in various transportation modes.
But every so often, the NTSB veers a little off-track, and issues a recommendation that generates more controversy than consensus. A prime recent example is the agency’s periodic campaign to persuade states to lower the legal threshold for alcohol-impaired driving.
Starting in 2013, the NTSB has been urging states to lower the current 0.08% blood alcohol concentration (BAC) definition of driving under the influence (DUI) down to 0.05%. The most recent instance came this January, in the NTSB’s annual “most-wanted” list – spelling out transportation safety improvements the agency says it would most like to see.
NTSB defended the “most-wanted” list’s call for lower state BAC thresholds as a way to cut highway fatalities and injuries (which, it concedes, has been made worse by over-the-counter, prescription and recreational drugs). Several decades ago, the agency had urged states to lower their BAC threshold for drunk driving to .08% (which at the time many states had set at .10% or higher).
The agency notes drivers’ ability can suffer some impairment even before their BAC hits .08% — a level at which the risk of an accident is twice that for a driver who has not consumed any alcohol. There’s some individual variation, but the lower BAC limit would likely reduce by half the amount of alcohol a person could drink and remain under the legal limit: one drink on average for women, and two for men.
The agency claims that a .05% BAC limit could reduce fatalities by 1,000; annual traffic deaths remain about 10,000 (about half the level from three decades ago). Most safety experts estimate about one-third of traffic deaths involve an alcohol-impaired driver.
The NTSB says its annual most-wanted list is its top advocacy tool, one meriting “more aggressive” efforts involving not just traditional and social media, but also networking with non-government organizations. But the call for lowering the BAC limit from .08% to .05% has failed to draw support from some you’d think would be obvious agency allies.
Mothers against Drunk Driving, for example, says it supports the current .08% BAC standard, and argues there are more effective ways to combat drunk driving than lowering the BAC limit to .05%. Some of these include requiring ignition interlocks for all DUI offenders, and sobriety checkpoints and other highly-visible enforcement efforts.
Some law enforcers also argue drivers with BAC levels between .05% and .08% account for a very small fraction of drunk-driving fatalities, so focusing on drivers with significantly higher BAC levels, or on repeat offenders, would far better-targeted steps, rather than defining large numbers of lower-risk drivers as DUI offenders.
While the lower BAC limit is the most controversial of the NTSB’s recommendations for fighting impaired or distracted driving, it’s just one of 19 recommendations the agency makes in that area. And since the NTSB has no power to enact or enforce the proposal, but must instead rely on its power to persuade state legislatures, it will have to build a better case before its recommendation is likely to receive serious attention in many states.