Interlocks Prevented 7,489 Drunk Driving Trips in Tennessee

On March 14, 2017, Mothers Against Drunk Driving (MADD) released our second annual Ignition Interlock Report. An interlock is a device about the size of a cell phone that is wired into the ignition system of a vehicle. If an interlock user is drunk, the vehicle will not start.

The report’s findings show that in the past year, these devices stopped 7,489 drunk driving trips in TennesseeIn the past decade, 44,966 trips were prevented.These drunk driving trips that were prevented equal injuries averted and lives saved.

Tennessee’s all-offender interlock law went into effect on July 1, 2013.  In 2016, a law was enacted to require interlock users to prove compliance while on the device before having it removed and being relicensed.  This means that as of July 1, 2016, all convicted DUI offenders must have an ignition interlock device on their car for 365 days AND that the last 120 days must be violation free before they can get their driver’s privelages re-instated.  In 2016, there were 5,787 interlock devices installed in Tennessee.

Interlock Facts:
•    Ignition interlocks are effective in reducing repeat drunk driving offenses by 67 percent. (CDC)
•    First time offenders have driven drunk at least 80 times before they are arrested. (CDC)
•    An ignition interlock is more effective than license suspension alone, as 50 to 75 percent of convicted drunk drivers continue to drive on a suspended license.All-offender interlock laws save lives reducing drunk driving deaths by 7, 12 and 15 percent. (McGinty, 2017. IIHS, 2012. Kaufmann, 2016.)
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