New study finds designated drivers not always sober

Car in a snowy ditch

Drunk driving is a problem of great concern nationwide, with almost 8 percent of all automobile accidents reported to law enforcement officials related to alcohol use, according to the Illinois Department of Transportation. The Illinois DOT also reports that about 310,000 people are injured every year in car crashes in which a driver is under the influence of alcohol. Accidents caused by drunk driving made up 36 percent of all fatal traffic accidents in the state during 2011.

In an attempt to reduce alcohol-related incidents, designated driving is pushed as a way to ensure that anyone out for a drink has a sober friend or group member available to drive them home. Incentive programs are used at some establishments to encourage the use of designated drivers by offering free sodas and non-alcoholic beverages. However, a new study from the University of Florida suggests that around 40 percent of designated drivers are not as sober as they claim.

Measuring Inebriation

The study – recently published in the Journal of Studies on Alcohol and Drugs – surveyed 1,071 people who were leaving bars in Gainesville, Florida, on six consecutive Friday nights between the hours of 10 p.m. and 2:30 a.m. Researchers gave the volunteers a short survey and then tested their blood-alcohol content with a breathalyzer. The volunteers who claimed to be designated drivers had lower BAC levels than those not driving, but the test showed that 41 percent had consumed alcohol.

The legal BAC limit in the U.S. is 0.08 – one of the highest in the world. The level at which driving becomes impaired is considered to be 0.02, but 18 percent of those in the study had BAC levels of 0.05 or above. The National Transportation Safety Board recently voted to recommend that the legal limit be lowered to 0.05 in all states, as studies have shown that driving is significantly impaired at that level and can result in car accidents.

Social Pressures

Looking at their findings, the researchers at the University of Florida hypothesized that social pressure could contribute to the increasing numbers of designated drivers who do not abstain from alcohol before driving a vehicle. A case in Virginia saw a 24-year-old man charged with motor vehicle homicide after driving drunk and texting while claiming to be the designated driver. Witnesses overheard the man admitting that he was drinking at a party before he left to drive his friend home.

In order to reduce the amount of fatalities caused by drunk driving, the researchers proposed an increase in national campaigns promoting the use of designated drivers who avoid alcohol completely before getting behind the wheel.