You are DUI in Montana if your blood alcohol content is .08% or higher. For drivers under 21, the limit it is .02%. Montana law provides that a person with an alcohol concentration of .04%, but less than .08% may be charged with DUI if that fact is considered with other competent evidence.
If convicted, not less than 24 consecutive hours or more than 60 days in jail.
Fine of not less than $100 or more than $500.
Six (6) month suspension of your license and/or driving privilege.
Parts of the imprisonment may be suspended, pending the completion of a court-ordered chemical dependency program.
If you refuse to submit to a blood or breath test, the peace officer may seize your driver's license. The license may then be suspended or revoked and the length of the suspension depends on whether it is a first refusal or second or subsequent refusal. (On first refusal, your driver's license is suspended for 6 months).
If you are convicted of first offense Driving Under the Influence (DUI) or Blood Alcohol
Concentration (BAC) with a BAC of .18 or greater, you will be ordered to install an ignition interlock device by the court (at your expense). The device prevents you from starting your car if there is any alcohol in your system.
If you receive probation, you may be eligible for a probationary license.
Under 21 (with a blood alcohol concentration of .02 or higher)
For a first offense, expect a fine not less than $100 or more than $500, and suspension of your driver's license for 90 days.
If you have a commercial license and had an alcohol concentration of 0.04% or more, you are subject to imprisonment for not more than 10 days, and a fine of not less than $300 or more than $1,000, plus a mandated license revocation.
Your insurance costs will probably increase considerably, perhaps for your entire family. Your insurance carrier may drop you, forcing you to find more expensive coverage. If you have to drive for your job, your employer's insurance rates may go up as well.
More Severe Consequences
More severe criminal actions are taken for DUI with a passenger under the age of 16 years, and DUI with an injury or a fatal crash.