Blood-alcohol content (BAC) levels are frequently part of news reports about charges of driving under the influence. Here’s some insight into why they’re used by police and prosecutors.
The National Institute on Alcohol Abuse and Alcoholism published the chart below showing possible impairment levels from various BACs in a pamphlet. But impairment can vary quite a bit from person to person, as the pamphlet points out:
“What tips the balance from drinking that has pleasant effects to drinking that can cause harm varies among individuals. Age, drinking experience, gender, the amount of food eaten, even ethnicity all can influence how much is too much.”
Over Drinking: Rough Guidelines
These charts are from the pamphlet “Alcohol Overdose: The Dangers of Drinking Too Much” published by the National Institute on Alcohol Abuse and Alcoholism (NIAAA), a part of National Institutes of Health, a federal agency.