Personal Liability And Legal Limits

Just because legal blood alcohol concentration (BAC) limit while drinking and driving in the United States is .08%, that doesn’t meet you’re off the hook if you get in a car crash with a BAC that’s less. You can still be sued for an accident at a BAC of .04%. So, the next time you get behind the wheel after a few drinks, remember you’re going to be held liable for your actions.

What is BAC?

BAC, or blood alcohol concentration, measures the weight of alcohol in your body per volume unit of blood, and it’s usually converted to a percentage. For instance, a person with a BAC of .10% would have alcohol in the body’s system that’s one-tenth the amount of blood in the system.

How Does BAC Affect Driving?

The Centers for Disease Control and Prevention report that a BAC of as little as .02% can affect your ability to drive a vehicle safely. For many people, a BAC of .02% is equivalent to having 2 alcoholic drinks, but this will vary from person to person according to weight and other factors, like the amount of time in which the drinks are consumed.

After 2 drinks, judgment declines and driving performance suffers; alcohol makes it harder for people to tackle multiple tasks simultaneously and react quickly to stimuli.

The Legal Limit Fine Line

Even though the legal limit for BAC is .08%, at .05% a person begins exaggerating behavior and losing coordination. This happens at about 3 drinks, which it’s roughly the point of inebriation when individuals have difficulty steering, remaining in lanes, and avoiding emergency situations (for example, debris in the roadway or cars coming toward you).

Drivers with a BAC of .05% are at high risk of being involved in a car accident, which begs the question of personal responsibility and liability, even when driving with a BAC that’s less than the legal limit.

Legally Drunk

After 4 alcoholic drinks, most individuals would be legally drunk and have a BAC of about .08%. One’s vision, reaction time, muscle coordination, hearing and speech are all impaired, and the intoxicated person may suffer from short-term memory loss. The alcohol in one’s system at this point is hindering perception and it becomes harder to judge vehicle speed or precise location of the vehicle.

This is the legal limit, remember. And, it’s a state of intoxication that severely puts the driver and others at risk. A BAC higher than this, which means someone has had 5 or more drinks within around 4 to 6 hours, will induce slurred speech, difficulty standing and a marked inability to remain in only one lane while driving. This point of drunk driving will likely cause serious harm to people, property, animals who might be on the road, as well as the driver’s life.

What Determines BAC?

Body weight, sex and period of time in which drinks are consumed, among other factors, determine a person’s BAC. In the United States, the National Institute on Alcohol Abuse and Alcoholism has determined that a standard drink, in terms of a unit to measure BAC, is equal to .6 ounces of pure alcohol. This is the amount of alcohol you will probably find in:

  • One 12-ounce beer with 5% alcohol content
  • One 5-ounce glass of wine with 12% alcohol content
  • One 1.5-ounce shot of 80-proof distilled spirit or liquor with 40% alcohol content

If you’re suspected of drunk driving, you’ll have to submit to a BAC test to determine if you were intoxicated while operating a motor vehicle. If your blood alcohol is more than the legal limit, you will be cited and likely arrested for a DUI. Considering the tremendous potential consequences of a DUI, it pays to not test the limits of the law and instead only operate a vehicle when you haven’t been drinking at all.

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