The device will randomly beep, thus informing the driver s/he needs to pick up the handset and blow into again. If s/he fails, then the IID will honk the horn, flash the lights, and make other alerts until the driver pulls over and turns off the vehicle. In no way does the device interfere with the vehicle’s operation.
After the driver stops the vehicle, s/he can retest his/her breath to permit normal vehicle operation.
Distracted driving
However, several studies discovered an alarming number of serious and fatal crashes caused by these rolling retests when the driver’s attention was diverted from the road to the device. Even though the National Highway Traffic Safety Administration’s (NHTSA) guidelines started out requiring drivers to stop their vehicles before the retests, nearly all vehicle manufacturers objected arguing that making a driver pull over is impractical and the rolling retests are safe.
Even across the country, there is little attention being directed to distracted driving due to IIDs. With the number of IIDs across the country having grown considerably from 133,000 to over 350,000 in the past decade with this number expected to increase even more especially with states—like Minnesota—requiring DWI offenders to install IIDs in their vehicles. Most states focus their distracted driving prevention efforts toward smartphones and texting with little regard for the distraction danger IIDs present.
Horror stories
To illustrate just a few serious accidents caused by distracted IID rolling retests, in Texas in 2017, a man who had been twice convicted of drunk driving had an IID installed in his vehicle. During a rolling retest, he dropped his interlock on the floor. So, he would have it in hand for the next retest, he reached down, fumbled for it, and struck a young woman who was backing out of her driveway. She died a week later. The man was sober; however, he pleaded guilty and received 18 years in prison.
In Pennsylvania, a driver performing a rolling retest blew so had he blacked out and hit a tree. In New Hampshire, another driver struck a telephone pole. In California, a man trying to do a rolling retest on a highway swerved across the dividing line and struck a vehicle, severely injuring one occupant and killing the other.