If I’m Arrested for DUI in Maryland, Will I Have to Use an Ignition Interlock Device?

Maryland has one of the most aggressive ignition interlock programs in the nation. The program began in 1989, and is fully automated and monitored by the Maryland Department of Transportation’s Motor Vehicle Administration. Maryland has the sixth-largest number of ignition interlock systems installed, a staggering statistic given that Maryland ranks 19th in population.


Since October 1, 2016, drivers are required to participate in Maryland’s Ignition Interlock Program for the following convictions:

  • Driving under the influence (DUI)
  • Driving while impaired (DWI) while transporting a minor younger than age 16
  • Driving while intoxicated with an initial breathalyzer test refusal
  • Homicide or life-threatening injury by motor vehicle while DUI or DWI

In addition to first-time convictions, interlock devices may be ordered for subsequent convictions. For instance, upon the suspension or revocation of your driver’s license, you may elect to participate in the Ignition Interlock System Program. Duration of enrollment depends upon circumstances, but state law states that you will enroll in the Ignition Interlock Program for:

  • 180 days if you submitted to a test indicating an alcohol concentration of at least 0.08 percent but less than 0.15 percent
  • One year if you submitted to a test indicating an alcohol concentration of 0.15 percent or more
  • One year if you refused to submit to the test

Maryland district courts, administrative law judges, or the Motor Vehicle Administration also may refer drivers to the program. A Maryland district court, the Office of Administrative Hearings, or the state Medical Advisory Board usually determines whether a driver is eligible for or must participate in the program and for how long.

Frequently Asked Questions About Ignition Interlock Devices

When faced with drunken driving charges, whether driving under the influence of driving while intoxicated, defendants may face the possibility of mandatory use of an ignition interlock system. For most people, this is new territory, and they have no idea what an ignition interlock system entails. What is an ignition interlock system?

  • An ignition interlock system is essentially a breathalyzer connected to the ignition system of your car.
  • It is designed to keep anyone under the influence of alcohol from driving the vehicle.
  • The driver must provide a breath sample by blowing into the interlock device before starting the vehicle.
  • If the breath sample submitted is below a pre-set state limit, the driver can start the vehicle. If the breath alcohol concentration is above the pre-set limit, the vehicle will not start.

The system does not affect the operation of the vehicle except to prevent its operation if the driver fails a breath test. When removed, the vehicle is returned to its original condition.

Interlock ignition system costs vary, but are roughly $70 to $150 to install and $60 to $90 per month for monitoring and calibration.

If You Were Arrested for DUI in Maryland, Contact the Criminal Defense Lawyers of Alpert Schreyer

If you were arrested for DUI or DWI in Maryland and may be required to use an ignition interlock device, consult a criminal defense attorney to determine what your rights are under the particular circumstances of your arrest.

The lawyers of Alpert Schreyer, LLC, can assist you in protecting your rights in these types of situations. Reach us at (866) 444-6363 or through our online contact form.

About Dianne Freed