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The main reason people continue to drive drunk today – despite 27 years of intense public education and law enforcement’s best efforts – is because they can. People with previous drunk driving convictions make up approximately one-third of the drunk driving problem in America.

Research shows that available breath alcohol ignition interlock devices are one of the most effective ways to keep convicted drunk drivers from continuing to drive drunk. Unfortunately, they’re significantly underused – currently there are only 135,000 vehicles with ignition interlocks nationwide. Interlocks are proven to be up to 90 percent effective, but it’s estimated that only one convicted drunk driver in eight gets the device each year – and most of those are repeat offenders.

We want to expand the use of interlocks to include all convicted drunk drivers. Even first-time offenses are indicators that a person has a serious problem with alcohol and is likely to become a repeat offender. First-time offenders have driven drunk an average of 87 times before they’re finally arrested.

Sixty-five percent of the public favors mandatory interlocks for first time offenders, and 85 percent of the public favor mandatory interlocks for repeat offenders. MADD is committed to turning that high level of public support into action.

Six states – New Mexico, Arizona, Illinois, Louisiana, Washington and Nebraska – have signed first offense interlocks into law. Contact your lawmakers and urge them to support lifesaving ignition interlocks for all convicted drunk drivers.  

 

 

Ignition interlocks prevent people who have alcohol in their system from driving a car. An operator breathes into an interlock device to determine blood alcohol concentration. If there is measurable alcohol in the blood, the vehicle does not start.

 



Current usage
Only one out of eight convicted drunk drivers each year currently gets the device. There are approximately 100,000 interlocks currently in service in the United States with 1.4 million DUI/DWI arrests made every year.

Effectiveness 
Research on ignition interlocks clearly shows their effectiveness. There are 12 high-quality studies on interlocks for repeat offenders, six high-quality studies on interlocks for first-time offenders and four meta-studies of multiple jurisdictions. All of these show decreases in repeat offenses while the interlock is on the vehicle. In Maryland, Alberta, California and elsewhere, offenders who were assigned interlocks had 50 percent to 90 percent fewer repeat offense than offenders who didn’t receive the device.

Interlocks fail when the supporting judicial infrastructure is weak—usually when mandatory interlock laws aren’t enforced or offenders who are sentenced to receive interlocks don’t have them installed or receive little oversight. MADD’s model interlock law, which has mandatory administrative and judicial components, will help eliminate many of these problems. You can learn more about MADD’s model law here. 

A Technological Solution
Stopping Drunk Driving Before It Starts

 

MADD’s Plans for Increased Use
 By working with legislators, judges, prosecutors and state driver license officials, the Campaign aims to stop repeat drunk drivers with interlocks. We’ll focus on significantly increasing interlock use in the next five years by encouraging states to enact model laws that require alcohol ignition interlock devices for all convicted drunk drivers.

We’ll also push for laws that require offenders to earn their way off the interlock device by passing all breath tests for a substantial and specified period of time. Even in New Mexico, where all first-time offenders are required to have ignition interlocks installed, an offender can attempt to drive drunk the day before the end of the court-appointed period and still get the interlock off the next day. By requiring no breath-test fails for a specified amount of time, we believe the device can help alter the offender’s high-risk behavior.

Click here to support ignition interlocks for all convicted DUI offenders.

Access the Washington State Ignition Interlock Demonstration Project.