Reducing Alcohol-Impaired Driving: Ignition Interlocks
"Ignition interlocks are devices that can be installed in motor vehicles to prevent operation of the vehicle by a driver who has a blood alcohol concentration (BAC) above a specified level (usually 0.02% – 0.04%). Interlocks are most often installed in vehicles of people who have been convicted of alcohol-impaired driving to give them an opportunity to drive legally.

Summary of Task Force Recommendations & Findings
The Task Force on Community Preventive Services recommends the use of ignition interlocks for people convicted of alcohol-impaired driving on the basis of strong evidence of their effectiveness in reducing re-arrest rates while the interlocks are installed. Public health benefits of the intervention are currently limited by the small proportion of offenders who install interlocks in their vehicles. More widespread and sustained use of interlocks among this population could have a substantial impact on alcohol-related crashes..."