Blood alcohol content (BAC)

Blood alcohol content (BAC) is the concentration of alcohol present in a person's blood. Blood alcohol content is the key measure which is used to determine the effect of alcohol on the body. The number of drinks that a person consumes is a poor measure of a person's level of intoxication. This is because a person's sex, weight, percentage of body fat, and individual body chemistry greatly influences the affect of alcohol on their body. The rate at which alcohol is consumed and the type of alcohol imbibed will also affect an individual's level of intoxication.

Blood alcohol content is used by law enforcement to determine the point at which a person is legally intoxicated, and thus, unable to safely operate a motor vehicle. In all US states, a person operating a motor vehicle with a blood alcohol content of 0.08 percent or above is considered intoxicated and can be charged with a driving under the influence (DUI), driving while intoxicated (DWI) or other related offenses.

Per se laws make it a crime to operate a motor vehicle with an illegal blood alcohol content. The arresting officer does not need to prove beyond a blood alcohol content test that a person was too intoxicated to be driving when pulled over. Implied consent laws also state that it is illegal to refuse chemical testing of your blood, breath, or urine to measure your blood alcohol content. These laws require that you submit to chemical testing at the request of a police officer. Failure to do so can enhance the penalties for a DUI/DWI and result in automatic vehicle sanctions.

There are special circumstances where the laws regarding blood alcohol content are slightly different. Most states have adopted strict zero tolerance laws in an effort to combat teenage drunk driving. These laws state that if a person under the age of 21 is caught with any level of blood alcohol content, they can be charged with a drunk driving offense. Even if a minor is not intoxicated by the amount of alcohol they consumed they can still be convicted of drunk driving.

There are enhanced penalties for any individual who is caught operating a motor vehicle with a blood alcohol content above a certain level. The specific blood alcohol content can vary by state, but in general the penalties for a drunk driving charge are enhanced when the DUI suspect has a blood alcohol content greater than 0.15 percent (in some states slightly higher). DUI offenders with a blood alcohol content at or above their state's enhanced penalty standards can face additional jail time, harsher fines, and more severe driver's license sanctions.

Blood alcohol content tests are not infallible and in certain cases their reliability can be challenged in a court of law. If you have been charged with a drunk driving offense because your blood alcohol content was above the legal limit, you would greatly benefit from speaking with a qualified DUI defense attorney. To learn more about blood alcohol content, please contact us to speak with an experienced DUI attorney can evaluate your case to determine how best to protect and maximize your legal interests.