The fact that 40% of all vehicle accident deaths in Montana involve alcohol mandates that the State adopt stiff drinking and driving penalties. And this does not include the financial impact of higher insurance rates―unlike other traffic violations there are no warnings. Justice is swift when it comes to driving under the influence (DUI) in Montana.

According to Montana law, DUI is defined by a blood alcohol or drug content (BAC) of .08% or higher. However, if an investigating officer finds your BAC to register between .04-.08%, you may still be charged with DUI if other concrete evidence (a swerving vehicle, running stop signs) leads the officer to conclude that you are drunk.

If interested, you can find full, legal-speak detail of the state's DUI policies in the Montana Code Annotated 61-8-401.

Top Penalties

First Time Offender with a BAC between .04-.08%

• Minimum sentence of 24 hours in a county jail

• Minimum fine of $300

Depending on the circumstances, this penalty can balloon to up to six months of jail time with a fine of up to $1,000. You can, however, get your sentence reduced pending the completion of a court-ordered chemical dependency education class.

Multiple Offender

• Up to 48 hours of immediate jail time

• Fines of up to $5,000

Following conviction mandatory jail time can be 30-365 days.

First-Time Offender with a BAC of .08% or Higher

• Minimum fine of $300

• Up to 10 days in the county jail

Fines may be doubled if a passenger under 16 years old is riding in your car.

Multiple Offender with a BAC of .08 or Higher

• Minimum fine of $5,000

• Up to six months in jail

Fines may be doubled if a passenger under 16 years old is riding in your car. Also, if you are convicted of a fourth DUI offense it is considered a felony and you may be slapped with fines as high as $10,000 and be heaved into jail for up to five years.

Under 21 Years Old with a BAC of .02% or Higher

• First Offense: fines between $100-$500; 90-day license suspension

• Second Offense: fines between $200-$500; six-month license suspension; up to 10 days in jail if over 18 years old

• Third Offense or Higher: fines between $300-$500; license suspended for one year; up to 60 days in jail

If convicted, you must also pay a $200 license reinstatement fee and register with an alcohol treatment program. The entire law for minors in possession (MIP) is defined in Montana Code Annotated 45-5-624.

Top Other DUI Notes

• Refusing an alcohol test will not buy you time. Instead, it will lead to an immediate suspension of your license.

• Open alcohol containers are prohibited in vehicles.

• If you are convicted more than once with a BAC of .16% or higher, you may be forced to install an alcohol interlock device in your car's ignition.

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