California readers may be surprised to discover that as many as 40 percent of those who volunteer as designated drivers still choose to consume alcohol before getting behind the wheel. Approximately one-fifth of designated drivers actually drink to the point of impairment, according to a recent study from the Journal of Studies on Alcohol and Drugs.
This revelation raises a lot of important questions about the degree of care that we expect from those who volunteer to be a designated driver, and whether consuming alcohol in any capacity is a violation of the promise to provide a safe and sober ride home. This issue goes to the core of the theory of negligence in personal injury law - which is that ordinarily we have no duty to act, but when we undertake some type of activity (such as driving) we must do so with a reasonable level of care and caution. To undertake an activity and then not exercise reasonable care is negligent.
While the legal limit for blood alcohol content is currently .08 in California, experts say that many drivers can become impaired at levels as low as .02. For a designated driver, this means not only staying below the legal limit but also being congizent of one's personal level of potential impairement that could put passengers at risk. If passengers relying on the designated driver are injured or killed in a car accident as a result of the driver's impariment, then there could be claim for personal injuries.
Source: CBS News, “Study: One-fifth of designated drivers impaired behind wheel,” Michelle Castillo, June 10, 2013