All drivers know that driving under the influence (DUI) is a serious crime, but do you know the exact circumstances that can lead to a DUI arrest and charges? Here are some of the specific things that may give rise to DUI charges:

If Your BAC Is Above 0.8

For a private motorist, the most obvious way to get arrested and charged with DUI is to drive with a BAC (blood alcohol content) of at least 0.08%. This means that for every 1000 ounces of blood in your body, 8 ounces of it is alcohol. This is the point at which the average person's driving is impaired after drinking alcohol. Therefore, if the authorities can prove that your BAC is at least 0.08, then they can convict you of DUI even without further evidence of impairment.

If Your BAC Is Above 0.4 and You Are a Commercial Driver

Commercial drivers are held to a higher standard of road safety than private drivers. One reason for this is because commercial vehicles tend to be huge and heavy; this means their capacity for causing serious injury and damage is huge. Therefore, commercial drivers have a lower BAC limit than private motorists; it's actually set at 0.04. Therefore, if there are two drivers, one a private motorist and the other a commercial driver both with a BAC of 0.04, only the commercial driver faces automatic DUI charges.

If There Is Any Alcohol In Your System and You Are a Minor

As a minor -- that is, if you have not reached the age of 21 -- you can be arrested and charged with DUI as long as there is any alcohol content in your blood. This is because minors aren't allowed to drink alcohol, minors cause a disproportionately high number of car accidents, and intoxicated minors cause even more accidents. For this reason, states have enacted a zero-tolerance law on minor DUI, such that any BAC above 0 is enough to get a minor driver arrested.

If You Appear Intoxicated or Your Driving Appears Impaired

Lastly, anyone can be arrested and charged with DUI even with a low BAC if their driving appears impaired. For example, if a police officer flags you down because you are driving erratically, they can charge you with a DUI even with a BAC of 0.06. This is because the main reason for DUI laws is to prevent drunk driving, and not to arrest people with particular BACs. Besides, the law recognizes that there are other drugs, including legal ones, which can impair driving other than alcohol. Therefore, you may be driving with a low BAC but your driving is impaired by other drugs.

If you're facing DUI charges, contact a DUI attorney in your area today.