Study Finds Ignition Interlocks Increase Auto Crash Risk By Up to 130%

California DMV Finds That Interlock Devices Yield No Reductions in DUI Offenses

SANTA FE, N.M. - New Mexico legislators interested in safer roads should think twice before requiring ignition interlock devices (IID) for those convicted of drunk driving, according to the American Beverage Institute (ABI). Dramatic findings in a recently released study by the California Department of Motor Vehicles (DMV) show that interlock devices had no statistically significant effect in preventing subsequent drunk driving convictions, but they increase their users' general crash risk by up to 130%.

For DUI first offenders, interlocks were so ineffective that the California DMV flatly stated, "there is no evidence that interlocks are an effective traffic safety measure for first DUI offenders," and concluded that "the use of the devices should not be emphasized."

Excerpts from the DMV report include the following:

• "The expected effect that an IID order/restriction issued by the court would result in a lower rate of subsequent DUI convictions was not observed." (p. 7)
• "The risk of a subsequent crash was higher for drivers installing an IID, compared to drivers not installing a device; drivers installing an IID had a risk of a subsequent crash that was 84% higher than drivers not installing an IID." (p. 10)
• "The results of this outcome study clearly show that IIDs are not effective in reducing DUI convictions or incidents for first DUI offenders ... Because there is no evidence that interlocks are an effective traffic safety measure for first DUI offenders, the use of the devices should not be emphasized." (p. 22)

ABI also noted that due to their exorbitant cost and intrusive nature, judges and legislatures traditionally have not imposed interlocks until the third DUI conviction. The California DMV's report confirms the wisdom of their approach.

"The results of this study raise some serious questions about the efficacy and safety of ignition interlocks for any population," said ABI executive director John Doyle. "The legislature should abandon this proposal and focus on meaningful solutions to New Mexico's drunk driving problem.".

To request a copy of the California DMV report, "An Evaluation of the Effectiveness of Ignition Interlock in California: Report to the Legislature of the State of California," contact Alison Preszler at 202.463.7110..

The American Beverage Institute is an association of restaurants committed to the responsible serving of adult beverages.