Second and Third DUI in Montana

A second or third DUI charge is a different kind of case from a first. Jail is mandatory, treatment is mandatory, and the court has to impose a vehicle sanction. But the first question I ask is whether it really is a second or third offense under Montana law. That depends on dates, on where the priors happened, and on what kind of convictions they were. Having worked inside a local prosecutor's office, I know the State sometimes counts priors that should not be counted, and a single prior falling out of the count can change the whole sentence. For an overview of Montana DUI law, start at our Missoula DUI defense page.

How Montana Counts Prior DUI Convictions

The counting rule is in MCA § 61-8-1011(1)(b). A prior counts for sentencing if less than 10 years passed between the previous conviction and the commission of the present offense. That 10-year window only limits a second offense. Once the new charge is a third or later offense, all previous convictions are used, with no time limit.

What counts as a prior conviction under § 61-8-1011(1):

• a final DUI conviction in Montana, in another state, or on a federally recognized Indian reservation;
• an unvacated forfeiture of bail or collateral;
• since 2025, a pending or later offense, if it results in a conviction before you are sentenced on the present offense;
• convictions under MCA § 45-5-104 (DUI-related negligent homicide), § 45-5-205 (negligent vehicular assault), and § 45-5-628(1)(e) (DUI-based child endangerment).

One important exception: a conviction for the under-21 offense (0.02 alcohol or any active THC) may not be counted as a prior (MCA § 61-8-1007(3)(b)). And if any prior was an aggravated DUI, a later ordinary DUI is sentenced at the aggravated level (§ 61-8-1007(1)(c), (2)(c)).

Second and Third Offense Penalties

As with a first offense, the penalty depends on whether the conviction is an impairment DUI, a per se DUI, or an aggravated DUI, and on whether a passenger under 16 was in the vehicle.

Source: MCA § 61-8-1007(1)(a), (2)(a), and (4)(a). Each cell shows the jail range, then the fine.

Mandatory Minimums Cannot Be Suspended

The minimum jail term may not be served under home arrest and may not be suspended unless the judge finds that jail would pose a risk to the person's physical or mental well-being (MCA § 61-8-1007(1)(d), (2)(d), (4)(b)). A court also may not defer imposition of sentence (§ 61-8-1011(4)). The time above the minimum is different: it may be suspended for up to 1 year while you complete a chemical dependency treatment program, and during that time the court can require DUI court or drug court, and 24/7 testing, where available (§ 61-8-1007(1)(e)). A DUI court may suspend all or part of a jail sentence, except the mandatory minimum (MCA § 61-8-1031(1)).

Required Treatment and Monitoring

A second or later conviction requires chemical dependency treatment, not just an education course (MCA § 61-8-1009(1)). Treatment must be followed by monthly monitoring for at least 1 year (§ 61-8-1009(9)(a)). You pay for it, and you may use health insurance (§ 61-8-1009(3)). Unfinished treatment also affects your license, as explained below.

Vehicle Sanctions Under MCA § 61-8-1010

On a second or later DUI conviction, the court shall choose one of three sanctions (MCA § 61-8-1010(2)):

• order participation in the 24/7 Sobriety Program or another court-approved testing program;
• if the court recommends a probationary license, restrict you to driving a vehicle with an ignition interlock during the probationary period; or
• order that each motor vehicle you owned at the time of the offense be seized and put through the forfeiture process. Seizure happens within 10 days after conviction (MCA § 61-8-1033(1)).

Which option the court picks is often something we can address at sentencing, depending on your work, your family, and your record. Driving a vehicle without a required interlock, or helping someone get around one, is a separate offense punishable by a fine of up to $500, up to 6 months in jail, or both (MCA § 61-8-1024(4)).

Your License on a Second or Third DUI

On a second offense within the § 61-8-1011 period, MVD suspends your license for 1 year. It cannot issue a probationary license until you complete at least 45 days and the court recommends one. On a third or later offense, the suspension is also 1 year, and the wait is at least 90 days. In both cases, if treatment is not complete at the end of the year, the suspension stays in effect until it is (MCA § 61-5-208(2)(b)(ii)-(iii)). Participating in 24/7 can let you get a probationary license without serving the waiting period (MCA § 44-4-1205(1)(b)), and a DUI court may authorize one (MCA § 61-5-231). See license suspension and hearings for the process.

Pretrial Conditions Can Start Right Away

With a prior DUI conviction in the 10 years before the current charge, a court can compel 24/7 participation and can make it a condition of bond or pretrial release (MCA § 44-4-1205(2)(a), (4)). That means testing may begin before your case is resolved.

How I Approach a Repeat DUI

I start with the record: the dates of each prior conviction, where it was entered, and what the conviction actually was. Then I review the new arrest the same way I would a first offense, including the stop, the field sobriety tests (I am certified in the NHTSA protocol officers use), and the breath or blood evidence. Depending on the facts, a disputed prior or a weak piece of evidence may change the charge, the sentence range, or which vehicle sanction is realistic. If your record could make this a felony, read our felony DUI page as well.

This page explains Montana law in general as of the 2025 Montana Code Annotated. It is not legal advice about your specific case.