A St. Louis DWI Defense Lawyer on Alcohol & Driver Impairment

There is much discussion about the hazards of drunk driving; however, the actual effects of alcohol on a potential motorist are often under-cited. Thus, whereas many people consume alcohol to get a desired physical or psychological effect, the vast majority of them do not understand how alcohol contributes to driver impairment.

Alcohol impairs driving in a number of ways.

Comprehension and Perception include being able to see, recognize, and understand signs, signals, and driving situations. Alcohol significantly impairs the driver’s ability to quickly interpret and respond to various situations while driving. Even a blood alcohol concentration (BAC) of as low as .04 contributes to driver impairment.

Concentration is the ability to shift attention among various stimuli which is common while driving as drivers must safely operate the vehicle, be watchful for other vehicles and pedestrians, and obey all traffic laws. Alcohol significantly impairs a driver’s ability to concentrate on these tasks, particularly vehicle speed, position, other traffic, and conversing with passengers, thus leaving him/her able to only focus on one task at a time. This divided attention leads to the inability to safely perform the numerous simultaneous tasks necessary for safe driving.

Coordination involves the ability to coordinate one’s fine and gross motor skills. The loss of coordination following alcohol consumption severely influences the speed and ability to react to potentially dangerous situations. Studies consistently demonstrate disturbance of gross motor skills with a BAC of .04, while more complex, fine motor skills decrease at .05.

Hearing/Vision Acuity. Being able to hear and see clearly is critical to safe driving. Alcohol influences a motorist’s hearing by muffling sounds, interfering with accurate identification of sound direction, and reducing the ability to hear. Most visual impairment occurs with a BAC as low as .03.

Judgment involves the ability to make responsible decisions; however, among the first thing alcohol hampers is one’s judgment, and significant decreases in judgment occur with a BAC as low as .02.

Reaction Time is the time between seeing and recognizing an object or event and the individual’s response to it. A BAC as low as .02 can reduce reaction time by as much as 15 to 25 percent, thus causing coordination and comprehension problems and resulting in accidents.

Vigilance and Attention involve the level of alertness and attention a driver is able to give to a particular task or object while driving. Studies demonstrate that a BAC as low as .005 can impede a driver’s attention and level of vigilance.

For more information, or if you or a loved one are in need of exceptional DWI defense in St. Louis, please contact us.