How Many Drunken Drivers Have Ignition Interlocks Stopped?

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CARS.COM — According to a new report released by Mothers Against Drunk Driving, ignition-interlock devices have prevented 1.77 million attempts to drive drunk nationwide. MADD released the report, which uses data from nearly a dozen major ignition-interlock providers, to underscore its effort to get every state to adopt laws requiring the devices on all drunken-driving offenders’ vehicles, starting with the first offense.

Related: DUI Fatalities Continue Decades-Long Slide

Ignition-interlocks prevent cars from being started unless drivers can prove via a built-in breathalyzer that they have no alcohol in their system. They are installed on the vehicles of offenders who have been convicted at least once of driving with a blood alcohol content at or greater than 0.08, the legal limit.

While all 50 states have some ignition-interlock requirement, only half mandate the device for all drunken-driving convictions, even a first offense. According to MADD, states that have implemented ignition-interlock devices have experienced major reductions in drunken-driving deaths — Arizona by 50 percent, Virginia by 40 percent, and Oregon, Washington and Hawaii by a quarter to a third.

MADD says interlocks are essential because simply trusting an offender to honor a license suspension isn’t enough. About a third of all drunken drivers arrested or convicted are repeat offenders; the average drunken driver has committed the offense 80 times before his or her first arrest and up to 75 percent of those convicted will continue to drive even on a suspended license, according to the organization.

“No other option available today – be it DUI court, treatment programs, license suspension, monitoring devices or twice-daily alcohol testing or alcohol ankle bracelets — can physically block an offender from operating his or her vehicle after consuming alcohol,” MADD said in a statement. “That’s why MADD believes every option for treatment and rehabilitation should include an ignition-interlock requirement to allow the offender to safely travel without putting others or themselves at risk.”

Among states that require all DUI offenders to use an ignition interlock, here are the total blocked attempts to start a car by a driver with a .08 BAC:

  • Alabama, 719
  • Alaska, 9,617
  • Arizona, 59,782
  • Arkansas, 40,521
  • Colorado, 92,503
  • Connecticut, 21,518
  • Delaware, 721
  • Hawaii, 6,445
  • Illinois, 96,456
  • Kansas, 58,497
  • Louisiana, 60,970
  • Maine, 5,185
  • Mississippi, 2,835
  • Missouri, 28,174
  • Nebraska, 22,178
  • New Hampshire, 8,850
  • New Mexico, 62,231
  • New York, 84,233
  • Oregon, 38,522
  • Tennessee, 26,613
  • Texas, 18,594
  • Utah, 8,066
  • Virginia, 10,067
  • Washington, 103,913
  • West Virginia, 15,046
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Former Assistant Managing Editor-News Matt Schmitz is a veteran Chicago journalist indulging his curiosity for all things auto while helping to inform car shoppers. Email Matt Schmitz

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