September 8, 2013

Blurry issue: Blood alcohol and driving

Expert opinion varies as the question of what constitutes impaired driving is up for debate.

By TED GREGORY/Chicago Tribune

(Continued from page 2)

Push to lower legal limit of intoxication to 0.05 stirs debate
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A volunteer driver takes the wheel at the University of Iowa National Advanced Driving Simulator in Coralville, Iowa, on Aug. 20.

Chuck Berman/Chicago Tribune/MCT

The metabolism of alcohol varies based on genetics, including variations in those enzymes, and environmental factors such as the amount a person drinks and his or her diet, the Department of Health and Human Services states.

"Regardless of how much a person consumes," a department report notes, "the body can only metabolize a certain amount of alcohol every hour," an amount "that varies widely among individuals and depends on a range of factors, including liver size and body mass."

Wider use of ignition interlocks is central to MADD's efforts. J.T. Griffin, the organization's senior vice president of public policy, said MADD supports 0.08 as the limit of legal intoxication in large part because research over 50 years shows definitively that everyone is seriously impaired at that level. Impairment below 0.08 becomes a little more uncertain.

Griffin said pushing to make 0.08 the law "was such a tough battle to fight. We sort of established it as the across-the-board level."

MADD is taking a more practical approach -- including recommending that ignition interlocks be mandatory for all DUI offenders -- in continuing its fight against drunken driving.

Twenty-one states and four counties in California require interlocks for all drunken driving offenders. In Illinois, first-time DUI offenders must obtain one if they want to drive.

"We're doing a lot of really positive things," Griffin said, "and we feel like we've got a lot of momentum. To shift to 0.05 really goes against what we're doing."


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