Tennessee DUI defense: Ignition interlock device requirements

Everyone knows that Tennessee law is tough on punishment for drunk drivers. Sentencing can include jail time, court costs, fines, loss or restrictions on driver’s licenses, and more. One more relatively recent addition to such penalties is the requirement that a defendant install an ignition interlock device or IID as a condition of receiving a restricted license as a result of a DUI conviction.

IID: mandatory or discretionary

With few exceptions, Tennessee law requires the installation and use of an IID following a DUI conviction if one wishes to obtain a Restricted Driver’s License. Anyone involved in a DUI investigation, charge or conviction should have a criminal defense attorney involved from the earliest stages of the process, but at the sentencing stage, legal counsel is essential. A lawyer will advocate for proper interpretation of Tennessee IID laws vis-à-vis the particular defendant’s criminal history, circumstances of the arrest and drunk driving incident in question.

The ignition interlock device

Basically, an ignition interlock is a small device that is integrated into the wiring of the internal technology that allows a vehicle to start. It is akin to a mobile breathalyzer, requiring a driver to blow into it and pass a breath test for alcohol content before the car will even start.

Tennessee DUI law requires that an ignition interlock be programmed to fail if the user’s blood alcohol concentration or BAC reaches 0.02 percent, at which level the vehicle will not start.

To prevent a defendant from using another person to provide the “breath” for an installed ignition interlock as a way to get around being monitored, Tennessee law requires that the device be equipped with the capacity to take a picture of the person breathing into the machine. Such a photo must also record the date and time taken.

It is, however, illegal for a defendant to ask someone else to blow into the device for the defendant. Tampering with the ignition interlock is also unlawful.

Other consequences of an IID requirement

A defendant who is required to install an ignition interlock must pay the associated costs, unless he or she is eligible for state assistance based on low income. In addition, anyone convicted of driving under the influence of alcohol or drugs in the state must pay an ignition-interlock fee of $40 to the state.

If a defendant is required to use an ignition interlock as a condition of driving, his or her Tennessee driving license will reflect that requirement. The law also imposes requirements regarding proof of installation, periodic reporting of proper function and device monitoring for “proper use and accuracy” at least every 30 days. Violation of these requirements must be reported to the court.

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