Ignition interlock requirements in Tennessee

Tennessee ties the device to the restricted license. When it applies, it runs for 365 days or the whole revocation, whichever is longer — and it only ends after 120 violation-free days at the end.

When the device is mandatory

In Tennessee the interlock usually arrives with a restricted license. A judge who approves a restricted license after a DUI conviction “shall also order the person to install and keep a functioning ignition interlock device as a condition of probation” if, at the time of the offense, any of these applied:

• the person had a blood or breath alcohol concentration of 0.08 or more, or alcohol in any amount combined with a drug or controlled substance;
• someone under 18 was in the vehicle;
• the person was in a reportable accident that was the proximate result of their intoxication; or
• the person violated the implied consent law and had a listed prior conviction or adjudication within five years.

If the court decides none of those applies, it must record specific findings of fact on the department's form — including the person's actual alcohol concentration. And the department will not accept a court order waiving interlock requirements that does not comply with the part.

When it is discretionary

For any DUI conviction, once the license is no longer suspended or revoked or where there is no prior conviction, a court may order a device “for up to one (1) year after the person's license is reinstated” — but only where it is not already required. A first offender who is eligible for a restricted license may also ask for a device in place of geographic restrictions on that license, paying all its costs.

Who cannot get a restricted license at all

The restricted license that the device usually rides on is not available to everyone. A person suspended for DUI is not eligible for one, and the court has no authority to grant it, if the department's record shows a prior conviction for vehicular assault, aggravated vehicular assault, vehicular homicide or aggravated vehicular homicide — or if the person seriously injured or killed someone in the course of the conduct that led to the DUI conviction. For that driver the restricted license waits until the mandated suspension has expired, even on a first conviction.

It is a condition of probation

Where a device is ordered under these provisions for a DUI or an implied-consent violation, the restriction must be a condition of probation or supervision for the entire period of the restriction. Breaking it is a probation matter as well as a license matter.

The setting, the record and the monitoring

Whenever a device is ordered, “the court must establish a specific calibration setting of two-hundredths of one percent (0.02%) breath alcohol concentration.” The court states the requirement and period on the record, notifies the agencies supervising the person, directs that the department's records show the restriction, and has a notation printed on the license. The supervising agency requires proof of installation, periodic reporting, and monitoring by an approved entity at least every thirty days.

One car, chosen in advance

A person who owns or drives more than one vehicle must elect the one they will drive exclusively during the interlock period and have the device installed before applying for any license, showing proof at the time of application. They may fit more than one vehicle. If the chosen vehicle stops being used, the replacement must be fitted and the authorities notified.

How long: 365 days or the whole revocation, and the final 120

Since July 1, 2016, every authorized removal “must be compliance-based.” The section defines the “ignition interlock usage period” as “a three-hundred-sixty-five-consecutive-day period or the entire period of the person's driver license revocation, whichever is longer,” and it ends with a final one-hundred-twenty-day period of violation-free use.

When the clock starts

The consecutive days start on the date of installation — provided the person applies for the restricted license within ten days of the court order authorizing it. Miss the ten days, or have no order, and the period starts on the date the interlock-restricted license is issued. A person who never applied for a restricted license during the revocation is not reinstated until they show proof of a current installation, and the full usage period then starts on reinstatement.

Fees the statute sets

Two fees are written into the chapter, separate from anything a provider charges. An ignition interlock fee of $40 is assessed for each DUI conviction for an offense on or after July 1, 2010, and a person applying for an interlock-restricted license pays a program development fee of $8.

The indigency fund

Tennessee runs an electronic monitoring indigency fund that pays eligible device costs for a person determined to be indigent. It does not pay for a device a first offender requested in place of geographic restrictions, whether or not that person is indigent.

Your data

Documents, records, monitoring data and other information a provider holds about a program participant are confidential and not available for public inspection.

The filing that runs alongside it

Tennessee's proof of financial responsibility runs for the length of the suspension or revocation rather than a fixed number of years, and certifies 25/50/25. The Tennessee SR-22 page covers it. The interlock usage period and the filing period are counted differently and do not end together.

What this page does not cover

Tennessee's DUI penalties, revocation lengths and provider licensing rules are in provisions this site has not read for this page. Device prices are set by providers; this site does not quote them.

Common questions