Criminal Defense & Social Security Disability Law

DUI 101: Driving with an ignition interlock device


Virginia requires all convicted drunk drivers to use an ignition interlock device in their vehicles, which prevents them from reoffending.

Drivers who are charged with a DUI in Virginia should be prepared to face harsh consequences if they are convicted. Virginia has some of the strictest penalties in place for DUI offenders, including fines, possible jail-time and driver’s license revocation. Most states in the nation have some type of legislation regarding ignition interlock device use. Virginia passed a law in 2012 requiring all convicted DUI offenders to have the devices installed in their vehicles. According to Mothers Against Drunk Driving, more than 8,500 vehicles in the state were equipped with interlock devices in 2013. Even more convicted drunk drivers have had the devices installed in their vehicles since then.

Operating a vehicle with an IID

Interlock devices are installed directly into the ignition system of the vehicle. Drivers must submit a breath sample into a tube connected to a small dashboard unit in order to start the car, according to TechHive. The IID measures how much alcohol is in the driver’s breath sample, and calculates the driver’s blood alcohol content level. If the driver’s BAC is below the preset limit, which is 0.02 percent in Virginia, then the car will start. Periodically during the ride, the driver will be prompted to blow additional breath samples into the tube. These rolling retests are required, and if one is missed, the device will sound an alarm until the car is pulled over and turned off.

A vehicle with an interlock device will lock up if a driver submits a breath sample that measures over 0.02 percent, or if the device is tampered with. Drivers who have attempted to start the vehicle and failed will be locked out for up to 15 minutes before they are able to retest. Those who are locked out a second time must wait for at least 30 minutes. This information is stored in the IID, and the driver may face additional penalties.

Drivers who have an IID installed in their vehicle should keep in mind that certain foods and mouthwashes can alter the breath test results. For instance, if the driver has recently brushed his or her teeth and used mouthwash, the IID may have a higher BAC reading. Breath test devices may pick up additional components in the breath sample, which could skew the results, according to the State University of New York at Potsdam.

When to contact an attorney

In addition to the penalties imposed by the Virginia court, convicted drunk drivers must live with a DUI on their record for years to come. A DUI can make it difficult to find a job in certain industries, obtain financing and get a professional license. If you face DUI charges, you may want to speak to an attorney in order to find out your legal rights and options.

Keywords: Virginia, DUI, drunk driving, ignition interlock