Legal sanctions, such as driver's license suspension and court-ordered alcoholism treatment, are designed to deter drinking and driving. Driver's license suspension and license revocation seem to be the most effective deterrents among the general driving population. However, a meta-analysis of deterrent strategies targeted to the drinking-and-driving population concluded that the most effective means for reducing rearrest for driving under the influence of alcohol (DWI, DUI) and crashes was a combination of license suspension and interventions such as education, psychotherapy/ counseling, and some follow-up.
Researchers contend that court-ordered treatment should be considered an adjunct, not an alternative, to license sanctions. According to Sadler and colleagues, a DUI, DWI conviction should serve to identify problem drinkers and guide or coerce them into alcohol treatment for DUI offenders can range from short-term educational sessions to therapy programs lasting at least 1 year.
Treatment of convicted drinking drivers normally emphasizes modifying drinking behavior. The type and duration of treatment depend on factors such as the severity of the person's drinking problem and DUI history. DUI offenders with less severe drinking problems benefit most from educational programs, although no known model is thought to be most effective in reducing recidivism or alcohol-related crashes. For repeat offenders or those with more severe drinking problems, therapy that lasts for at least 12 months and that includes intensive programs focused on the individual appears to be most effective.
Driving involves multiple tasks, the demands of which can change continually. To drive safely, one must maintain alertness, make decisions based on ever-changing information present in the environment, and execute maneuvers based on these decisions. Drinking alcohol impairs a wide range of skills necessary for carrying out these tasks. This Alcohol Alert examines alcohol impairment of driving skills and describes some factors that increase motor vehicle crash risk.
According to National Institute on Alcohol Abuse and Alcoholism, drinking and driving claims more than 15,000 lives annually.
The proportion of alcohol to blood in the body is expressed as the blood alcohol concentration (BAC). In the field of traffic safety, BAC is expressed as the percentage of alcohol in deciliters of blood--for example, 0.10 percent (i.e., 0.10 grams per deciliter). A 160-pound man will have a BAC of approximately 0.04 percent 1 hour after consuming two 12-ounce beers or two other standard drinks on an empty stomach.
All State laws stipulate driver BAC limits, which now vary by State. According to these laws, operating a vehicle while having a BAC over the given limit is illegal. The BAC limit for drivers age 21 and older in most States is 0.10 percent, although some States have reduced the limit to 0.08 percent.
The many skills involved in driving are not all impaired at the same BAC's. For example, a driver's ability to divide attention between two or more sources of visual information can be impaired by BAC's of 0.02 percent or lower. However, it is not until BAC's of 0.05 percent or more are reached that impairment occurs consistently in eye movements, glare resistance, visual perception, reaction time, certain types of steering tasks, information processing, and other aspects of psychomotor performance.
Alcohol Impairment Chart
blood alcohol level by body weight
WOMEN
MEN
The National Highway Traffic Safety Administration (NHTSA) credits State laws raising the legal drinking age to 21 with preventing almost 1,000 traffic deaths annually. Legislation to reduce the BAC limit to 0.02 percent or lower, referred to as the "zero tolerance law" for young drivers, has been passed by 29 States and the District of Columbia to reduce alcohol-related fatalities further. The National Highway Systems Act provides incentives for all States to reduce their BAC limits for drivers under 21 to 0.02 percent beginning October 1, 1998.
One study examined the effectiveness of lowering BAC limits for young people in States where such laws have been in force for at least 1 year. The researchers found that after the BAC limits were lowered to 0.00 or 0.02 percent, the proportion of nighttime fatal crashes involving single vehicles in this age group dropped 16 percent.
- In 2007, an estimated 12.7 percent of persons aged 12 or older drove under the influence of alcohol at least once in the past year. This percentage has dropped slightly since 2002, when it was 14.2 percent. The 2007 estimate corresponds to 31.4 million persons. From 2006 to 2007, the rate of driving under the influence of alcohol among young adults aged 18 to 25 decreased from 24.4 to 22.8 percent.
- Driving under the influence of alcohol was associated with age in 2007. An estimated 7.8 percent of 16 or 17 year olds, 18.3 percent of 18 to 20 year olds, and 25.8 percent of 21 to 25 year olds reported driving under the influence of alcohol in the past year. Beyond age 25, these rates showed a general decline with increasing age.
- Among persons aged 12 or older, males were nearly twice as likely as females (16.6 vs. 9.0 percent) to drive under the influence of alcohol in the past year.
