Montana DUI With a Learner Permit: Under-21 0.02 Rule, DUI Penalties and License Effects

Montana has separate alcohol and drug rules that can affect a learner-permit holder. For drivers under 21, an alcohol concentration of 0.02 or more is a separate offense with its own penalty structure; standard DUI provisions have different elements and penalties. The licensing effect depends on the actual offense, conviction, and any separate administrative action.

Under-21 0.02 Rule and Related Penalties

For drivers under 21, Montana's 0.02 alcohol rule is separate from the standard DUI statutes. A first conviction under the under-21 0.02 provision can bring a $100-$500 fine, a 90-day suspension, and court-ordered chemical-dependency education or treatment.

Under 18: a traffic or alcohol/drug violation also affects GDL advancement because the teen must have a clean six-month period before moving beyond the learner stage. Do not apply that teen GDL rule to every permit holder under 21.

Can a Driver Under 21 Get a DUI With a BAC Below 0.08 in Montana?

Yes. A driver under 21 can face Montana's separate 0.02 alcohol-concentration offense even below 0.08, and an impairment-based DUI can also depend on the driver's actual impairment rather than only a single BAC number.

Does Montana's Under-21 Zero-Tolerance Law Apply to THC?

Montana's under-21 statute also separately addresses detected THC. Do not treat the alcohol 0.02 threshold as the only substance rule that can affect an under-21 driver.

Criminal Penalties and Legal Proceedings

Do not combine the under-21 0.02 offense with the penalties for standard DUI. For a first standard impairment-based DUI under MCA 61-8-1002(1)(a), the jail term includes at least 24 consecutive hours and can extend up to six months, plus the applicable fine. Twenty-four hours is not the maximum.

The under-21 0.02 offense has its own court and treatment requirements. It also may not be counted as a prior conviction under the ordinary DUI repeat-offense penalty provisions.

What Happens if a Montana Permit Holder Refuses a DUI Chemical Test?

Montana's implied-consent rules can create a separate administrative license consequence when a qualifying chemical test is refused. That process is separate from any criminal DUI charge, so the driver may face licensing action even before the criminal case is resolved.

Long-Term Impact on Licensing and Insurance

Long-term consequences depend on which alcohol offense was actually charged and convicted. Keep the under-21 0.02 offense separate from standard DUI when discussing repeat offenses, licensing consequences and criminal penalties.

For insurance effects, use the dedicated Insurance Cost Impact guide. For reinstatement requirements after a suspension or revocation, follow the current Montana MVD instructions for the specific case.