How Does an Ignition Interlock Device Work?

Several years ago, Arizona passed a law that allows some persons arrested or convicted of driving under the influence of alcohol (DUI) to regain limited driving privileges. Since the rules can be complex, experienced Arizona DUI defense attorneys study them carefully to ensure each client knows his or her options. One requirement drivers may have to face in order to get driving privileges back is the installation of an ignition interlock device on their vehicles.

What is an Ignition Interlock Device?

An ignition interlock device is similar to the breath testing devices police use to check the blood alcohol levels of drivers pulled over on suspicion of DUI. It attaches to the ignition of the vehicle, and it requires the driver to provide a breath sample. Without a breath sample that tests negative for alcohol, the vehicle will not start. Some devices also require periodic “rolling tests,” which take place while the vehicle is out and about.

If a driver fails to give a breath sample or gives a sample that is positive for alcohol, the device will typically issue a warning. If the car is off, the vehicle will not start; if the engine is turned on, the horn may sound and the lights may flash, which can be turned off only by turning off the ignition. Most interlock ignition devices do not turn off the ignition automatically after a failed rolling test, since this may lead to a serious car accident.

The costs of having an ignition interlock device installed and maintained can be steep, and they are typically paid by the driver. An experienced Arizona criminal defense lawyer can help you determine if an ignition interlock device is an option for you and what costs you may face.

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About the Author

Zachary Mushkatel discovered his affinity for the law by chance. As a political science major at the University of Arizona, he first aspired to become a professor. But an unexpected invitation to participate on a mock trial team at the university encouraged him to turn his competitive spirit and drive…