In 2011, 9,878 people were killed in drunk driving-related traffic accidents. Of those fatalities, 6,507 were drivers with a blood alcohol concentration (BAC) of 0.08 or higher. According to the National Highway Traffic Safety Administration (NHTSA), drivers with a BAC of at least 0.08 involved in fatal car crashes that year were seven times more likely to have a previous drunk driving conviction than sober drivers, indicating that repeat offenders pose a serious risk of reoffending. A study by the Centers for Disease Control and Prevention (CDC) found that first-time DUI offenders have driven drunk at least 80 times before being arrested, suggesting that even first-time drunk driving offenders are likely to repeat the offense in the future.
Both the CDC and NHTSA highly recommend the use of ignition interlock devices (IID) to reduce repeat offenses, recidivism, and drunk driving-related deaths and injuries. Research conducted on the effectiveness of ignition interlocks over the past 20 years consistently proves that IIDs reduce repeat offenses and recidivism among both first-time and repeat DWI offenders by 50 to 90 percent while installed, according to NHTSA. Many studies have also been conducted on individual states’ interlock programs. A 2004 study on New Mexico’s interlock program showed a 50 percent reduction in recidivism among first-time offenders using an IID while a 2003 study on Illinois’s interlock program showed an 85 percent reduction in recidivism among repeat offenders who installed the device.
More importantly, IIDs and the decrease in repeat DWI offenses have significantly reduced drunk driving-related deaths and injuries. States that require all drunk driving offenders to install an IID in their vehicle, including Arizona, Oregon, New Mexico, and Louisiana, have seen at least a 30 percent reduction in drunk driving-related deaths, as reported by Mothers Against Drunk Driving (MADD).
In addition to reducing recidivism, IIDs:
- Allow DWI offenders to maintain a legal driving status so that they can work, complete alcohol treatment, and remain productive citizens
- Help predict future DWI recidivism risk based on failed BAC tests
- Teach DWI offenders to drive without drinking
- Provide a safety net for setbacks and relapses during alcohol treatment
- Cost less than incarceration or electronic monitoring and save the public money
However, once the ignition interlocks are removed, recidivism rates increase to rates similar to those of offenders who didn’t install the device, causing researchers to suggest long-term or permanent IID installation as a condition of driving for repeat offenders.