Image: Intoxicated driver © rolfo, Flickr, Getty Images

While a single drunken-driving conviction is traumatic and expensive enough to sober up most drivers, about one-third of all drunken-driver arrests are of people who are repeating their crime, according to the National Institutes of Health.

The most egregious offenses make headlines, such as the case of the woman arrested in two DUIs in the same day and the man accused of his 11th drunken-driving offense after dangerously passing a school bus.

Or consider this Florida man, charged with his seventh DUI. His driver's license has been permanently revoked and he can't register a car in his name, which prevents him from getting auto insurance. Yet he continued to drive and now faces up to 17 years in prison if convicted.

How do multiple DUI offenders keep driving?

"That's the question," says Jan Withers, national president of MADD, or Mothers Against Drunk Driving. "Why do people do it? They do it because they can."

Taking away everything but freedom

The levers that society uses to control impaired driving haven't proved especially effective against problem drunks.

Losing your license: A first DUI conviction will bring a license suspension of at least 30 days in every state. In most states, you also will visit a jail cell. After a third conviction, jail terms can reach a year and the suspension can last as long as eight years. After a fourth conviction, many states revoke your license permanently or treat the conviction as a felony, with prison sentences that can stretch to 10 years.

In a society that wants to treat drunken driving as a mistake rather than a crime, even the threat of jail time isn't enough to stop people from driving while intoxicated, Withers says.

Depending on which study you come across, the average person convicted under DUI laws drives drunk anywhere from 50 to 200 times before getting caught. Even after a conviction for driving drunk, 50% to 75% of people whose licenses have been suspended continue to drive, Withers says.

Losing your insurance: A first-time DUI conviction can easily triple your car insurance rates and earn you an SR-22 requirement. A repeat DUI conviction on your record, depending on the look-back rules your state and insurance company use, easily can bring a cancellation.

You need a valid driver's license to find insurance coverage, but some drivers will slip through the cracks with a suspended license. For example, some insurance companies won't run a background check on a customer until a claim is filed, says George Creal, a Georgia attorney who has represented thousands of DUI clients.

"Not all insurance companies will run your driving history on an annual basis," Creal says. Even if they do and decide not to take the risk, a driver with multiple convictions but a valid license can find coverage in a state's assigned-risk pool. Creal says he has seen clients with five DUI convictions driving legally.

An estimated 15% to 25% of drivers don't buy auto insurance anyway, so losing insurance coverage after a DUI conviction isn't much of a hindrance to them, says Robert Hunter, director of insurance at the Consumer Federation of America.

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