So, what does work?

One of the best ways to stop people from driving drunk is requiring ignition interlocks, which prevent the car from starting if the driver registers a blood alcohol level of 0.02%, Withers says. Thirty-two states require interlocks for first offenders, according to a MADD report. The devices allow drivers to keep their cars so they can drive to work, but prevent them from driving while drunk, Withers says.

The National Highway Traffic Safety Administration estimates ignition interlocks would reduce recidivism by 75% and alcohol-related fatalities by 7%.

Here are some other prevention tactics NHTSA has looked at, and estimates of success:

  • Automobile impoundment: Many states automatically impound a DUI suspect's car for 12 to 24 hours to prevent the driver from climbing immediately back behind the wheel. Other states have adopted more aggressive seizure laws -- even selling repeat offenders' cars. These tactics decrease recidivism by an estimated 38% and DUI crashes by about 4%.
  • Electronically monitored house arrest: This tactic can require offenders to relay a breath test when prompted by a random phone call. The program decreases recidivism by an estimated 31%, causing DUI crashes to decrease by about 3%.
  • Intensive probation supervision with treatment: Decreases recidivism by an estimated 48%, causing DUI crashes to decrease by 4%.
  • Intensive sobriety checkpoint program: Highly visible sobriety checkpoints would reduce alcohol-related fatalities by at least 15%.
  • Enforcement of intoxicated-patrons laws: Using undercover police officers to enforce the state laws against serving alcohol to intoxicated bar and restaurant patrons would reduce alcohol-related crash fatalities by an estimated 11%.
  • Server training: Training bar employees to prevent patrons from driving drunk could reduce nighttime DUI injury crashes by 17%. An estimated 40% to 60% of intoxicated patrons drive after consuming alcohol in bars, clubs or restaurants.

Alcohol-related crashes accounted for an estimated 18% of the $103 billion in U.S. auto insurance claims, according a 2000 study by NHTSA. Reducing alcohol-related crashes by 10% would save $1.8 billion in claims payments and loss adjustment expenses.

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