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The United States has a national blood alcohol concentration (BAC) standard of .08 that is based on more than 30 years of scientific evidence.
The science on how alcohol affects a person’s driving skills has evolved over the past 30 years which has led the National Highway Traffic Safety Administration (NHTSA) to establish the .08 standard.
Although outward appearances may vary and some subjects may feel that they are well in control, virtually all drivers are impaired at .08 BAC. Laboratory and on-road research shows that the vast majority of drivers, even experienced drivers, are impaired at .08 BAC in critical driving tasks such as braking, steering, lane changing, judgment, and divided attention.
These numerous studies prompted the distilled spirits industry to universally support the passage of .08 BAC laws as part of a comprehensive solution that included BAC education and public awareness of the law.
Blame robust scientific study and the makers of alcoholic beverages for agreeing on this standard based on 30 years of solid evidence that it is sound.
Your reality of conclusion may vary...but the validity of that conclusion is not supported by fact.