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Blood alcohol content is expressed as a percentage of alcohol in the blood—as an example, if a person has a BAC of 0.10, then one-tenth of one percent of that person’s blood, by volume, would be alcohol. All states except Utah have set 0.08% BAC as the legal limit for DUI. (Utah very recently lowered their threshold to 0.05%, a change which went into effect on December 30th). For commercial drivers, the limit is 0.04%, and in most states, for those under 21, there is a zero-tolerance limit, meaning any amount of alcohol could result in a DUI arrest.
The exception to the 0.08% BAC is in the state of Arizona, where you can be charged with DUI with any level of alcohol in the body if your driving exhibits any degree of impairment. This means that while the presumption of impairment is 0.08% in Arizona, showing signs of impairment in your driving ability could still get you arrested and convicted, even if your BAC is less than 0.08%.
Changes Coming to BAC Levels?
A scientific panel has recently recommended that all states lower their current BAC thresholds to 0.05 percent as a means of preventing the 10,000 or more deaths in the U.S. each year due to alcohol impairment. This report—a full 489 pages—was commissioned by the U.S. government, and contains multiple recommendations, in addition to lowering the current BAC levels. Studies have shown that the United States lags behind other developed nations in their efforts to prevent drunk driving fatalities.
In fact, more than 100 other countries have already adopted the 0.05 BAC threshold. In Europe, after putting the new law in place, the number of traffic deaths associated with impaired drivers was reduced by more than half within ten years. The National Transportation Safety Board is in agreement with reducing the BAC levels, although, predictably, the alcohol industry is pushing back.
Alcohol and Restaurant Industries Opposed to the Change in BAC Levels
When Utah lowered their BAC threshold, the beverage institute took out a full-page ad in the newspaper proclaiming “Utah: Come for vacation, leave on probation.” The alcohol and restaurant industries believe lowering the BAC threshold would do nothing to deter repeat drunk driving offenders or high BAC drivers, which they believe represent the vast majority of drunk-driving fatalities.
How Much Alcohol Equals a 0.05 Percent BAC?
There are several factors which determine how much alcohol a person would have to drink to reach the proposed 0.05% BAC. A person’s size, gender, medications they are taking, and whether they have recently eaten all have bearing on the BAC level. As an example, a 200-pound man might be able to drink three beers and not be over the proposed 0.05 limit, while a 115-pound woman, might exceed that limit with only one alcoholic drink, particularly if she had not eaten recently.
Recommendations for Alcohol Taxes to Increase and to Make Alcohol Less Available
The new report has also recommended increases in state alcohol taxes as well as making alcohol less available by reducing the days and hours of alcohol sales in restaurants, bars and stores. The report claims that doubling the current alcohol taxes could result in an 11 percent reduction in the number of alcohol-related traffic deaths, although some question this number. Finally, the report calls for placing limits on alcohol marketing and cracking down on sales to those who are under the age of 21, or who are already intoxicated, under the belief that these changes would result in a decrease in binge drinking.
The push to lower the BAC threshold is likely to continue, particularly after Utah put the lower threshold in place, but it remains to be seen whether the other states in the U.S. will follow the suggestions made by this new report.
