This chapter presents information on the prevalence of underage drinking and impaired driving, factors that are associated with these offenses, and their consequences.

Prevalence of Drinking Among Youth
Despite a minimum legal drinking age of 21, many young people in the United States consume alcohol. In 1997, 25 percent of 8th graders, 40 percent of 10th graders, and 53 percent of 12th graders reported drinking alcohol during the 30 days prior to being surveyed (University of Michigan 1997). (See Figure 2-1)

Binge drinkingoften defined for males as having 5 or more drinks in one sitting and for females as having 4 or more drinks in one sitting¹ is reportedly widespread among youth. Binge drinking often begins around age 13, tends to increase during adolescence, peaks between the ages of 18 and 22, and then gradually decreases (NIAAA 1997). Binge drinking at least once in the 2 weeks before the survey was reported by 15 percent of 8th graders, 25 percent of 10th graders, and 31 percent of 12th graders in 1997 (University of Michigan 1997) (see figure 2-1).

Prevalence of Drinking and Driving Among Youth
Not only is drinking a prevalent problem among youth, but many of those who drink also drive after drinking. Fifteen percent of students in grades 9–12 (ages 15–18) surveyed in 1995 reported driving after drinking during the month before being surveyed, and more than one-third reported riding with a driver who had been drinking (Centers for Disease Control and Prevention 1996). A projected increase in the population of American youth may result in an increase in underage drinking and impaired driving. The U.S. Census Bureau estimates that in the year 2000, the population of 15- to 20-year-olds will be 23.9 million, an increase of almost 2 million from 1996. The youth population is expected to increase by almost 14 percent by the year 2005 (NHTSA 1998a) (see figure 2-2).

Impaired driving is especially prevalent among college students who binge drink. One survey found that 44 percent of college students reported binge drinking at least once during the 2 weeks before being surveyed, and about 19 percent reported frequent binge drinking (i.e., binge drinking three or more times during the 2 weeks prior to the survey). Drinking and driving during the 30 days before the survey was reported by more than 60 percent of the men and by almost 50 percent of the women who were frequent binge drinkers, compared with 20 percent of the men and 13 percent of the women who were non-binge drinkers (Wechsler et al. 1994).

¹ A standard drink is 12 grams of pure alcohol, which is equal to one 12 ounce bottle of beer or wine cooler, one 5 ounce glass of wine, or 1.5 ounces of 80 proof distilled spirits.

Alcohol-Related Crash Risk Among Youth
Compared with adults, young drivers are overrepresented in all fatal crashes as well as crashes involving alcohol. For every 100,000 licensed drivers, sixty-six 15- to 20-year-old drivers were involved in fatal crashes (including those involving alcohol), compared with 28 adult drivers in 1996. For fatalities involving alcohol, 14 young drivers were involved in fatal crashes for every 100,000 licensed drivers, twice the rate for drivers 21 and older (NHTSA 1998a). Twenty-one percent of the 8,054 drivers aged 15- to 20 involved in fatal crashes in 1996 had positive blood alcohol concentrations (BACs), including 7.4 percent that had BACs between 0.01 percent and 0.09 percent, and 13.8 percent that had BACs of 0.10 percent or higher (NHTSA 1998a).

Young drivers' greater crash risk is attributed, in part, to their lack of driving experience, which renders them less able than more experienced drivers to cope with hazardous situations even when they have not been drinking (Mayhew et al. 1986). When young drivers do drink and drive, they are more vulnerable than adults to the effects of alcohol on driving ability. For all drivers, each 0.02 increase in BAC nearly doubles the risk of being involved in a fatal crash. For drivers ages 16–20, the risk of a fatal crash increases even more with each 0.02 percent rise in BAC (Mayhew et al. 1986; Zador 1991; NIAAA 1996a). The estimated crash risk for male drivers ages 16–20 is at least three times higher than the risk for male drivers age 25 and older at all BAC levels (Zador 1991).

In 1995 law enforcement agencies made nearly 15,000 DUI arrests of persons under age 18. In 66 percent of these arrests, the youth was 17 years old, and in 3 percent the youth was under age 15. Juveniles arrested for DUI were disproportionately male (84 percent) and white (91 percent) (Snyder 1997a).

Under-21 Access to Alcohol
In 1997, 75 percent of 8th graders and 89 percent of 10th graders reported that alcohol is "fairly easy" or "very easy" to obtain (University of Michigan 1997). In a 1987 study, researchers reported that 18- to 20-year-old males successfully bought beer in retail outlets (i.e., liquor stores and convenience stores) in 97 percent of attempts in Washington, DC; 80 percent of attempts in Westchester County, NY; and 44 percent of attempts in Albany and Schenectady Counties, NY (Preusser and Willams 1992). Other research conducted with women who were at least 21 but appeared younger found that the women were able to buy alcoholic beverages in stores, restaurants, and bars without showing identification in about 50 percent of their attempts (Forster et al. 1995; Grube 1997).

The rate at which juveniles are arrested for liquor law violations is quite low. In 1996, law enforcement agencies made only 518 liquor law violation arrests for every 100,000 persons 10 to 17 years old in the resident population (Snyder, unpublished data, 1998). The youth population will undergo rapid growth in the early part of the next decade (see Figure 2-2). Thus, a focus on preventing youth DUI and other alcohol-related offenses among this group will have an amplifying effect.