Tennessee residents may know that getting behind the wheel after a night of drinking is a bad idea, but they might not realize how much even small amounts of alcohol can impair drivers. Motorists generally face drunk driving charges when toxicology testing reveals blood alcohol levels of .08 percent or higher, but data from the Centers for Disease Control and Prevention indicates that the driving skills of a man weighing 160 pounds would begin to decline after consuming just two drinks in an hour.
Motorists with a BAC level of .02 percent may feel relaxed and in control, but their judgment, reflexes and multitasking abilities will be comprised according to the CDC. The third drink in an hour raises the blood alcohol level of a 160 pound man to .05 percent, which further degrades response times and may make steering more difficult. Drivers with a BAC level of .05 percent also have reduced coordination and may find it more difficult to track moving objects.
Drivers with blood alcohol levels of .08 percent are usually seriously impaired. They may find it difficult to accurately judge the speeds of other vehicles and their balance, judgment and concentration will all be affected. A BAC level of .15 percent causes diminished muscle control, and drivers this intoxicated could find it hard to properly focus on the road ahead.
Blood alcohol levels are usually determined by breath or blood tests. While scientific evidence of this type may seem compelling, it can be challenged by criminal defense attorneys in certain situations. The sophisticated electronic equipment used to conduct breath tests may provide artificially high readings if it has not been properly maintained, and even the results of blood tests could be unreliable if the sample used is mishandled or contaminated.