Intoxication is measured by the percent of alcohol in the blood. The typical definition of intoxication used to be a blood alcohol concentration (BAC) of 0.10 percent, but in the first few years of this century, almost every state lowered the level to 0.08 percent as a condition of receiving federal highway-construction funding. (More about federal dollars in a moment.) To some extent, the size of the person affects his or her blood alcohol level: Assuming the same quantity of alcohol has been consumed, the heavier a person’s body weight, the lower the percent of his or her blood alcohol. This is because alcohol mixes with the water in the body. This, in turn, is why women, who naturally have less water and a higher percentage of body fat than men, tend to have higher blood-alcohol contents than men of similar height and weight who have consumed the same amount of alcohol. The alcohol is more highly concentrated in the women’s bodies than the men’s