Why is .08 the Legal Limit?

Drunk driving is a huge problem in every state. Between 2013 and 2015 in Missouri, people between the ages of 21 and 25 were most likely to die as a result of drunk driving, according to data from the Missouri Department of Transportation.
You can technically drive on roadways as long as your blood alcohol content is less than 0.08 percent. However, the only truly safe BAC is zero. Someone with a BAC of 0.04 could still feel inebriated and be a danger on roadways. This begs the question: Why is the legal limit of alcohol 0.08?
It varies throughout history
The legal limit has not always been 0.08. In recent decades, some states had the legal limit set at 0.1 or even 0.15. Thanks to efforts from organizations such as Mothers Against Drunk Driving, the federal government took official action to set it much lower at 0.08. In 2000, Congress enacted legislation to withhold transportation funding to states that did not comply to the new limit. By 2004, every state set 0.08 as the official designation of drunk drivers.
People have different limits
One might assume that 0.08 is the point where most people start feeling tipsy or drunk. In actuality, there is no magic number that states when a person will officially be a danger. A variety of factors ultimately influence an individual person’s BAC, such as weight, gender and body fat percentage. One person may feel completely wasted with a BAC of only 0.05 while another can feel completely fine with a BAC of 0.15.
When do people reach the limit?
As stated above, it depends on the individual person. Some people can have three drinks within a couple hours and be completely fine. Others can drink the same amount and come in well above the 0.08 limit. The best advice is to always err on the side of caution. If you drink a substantial amount in one evening, then you are better off finding another way to get home.

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