What Are the Montana DUI Laws?

Each state has its own drunk driving laws that prohibit driving under the influence of drugs or alcohol. These DUI laws vary from state to state but generally make it a crime to drive with a blood alcohol concentration of 0.08 or greater. The table below outlines Montana's main DUI law.

Code Section

Montana Code section 61-8-401: Driving Under the Influence of Alcohol or Drugs

What's Prohibited?

It is illegal for a person who is under the influence of alcohol, a dangerous drug, or a combination of both to drive a vehicle (or to be in actual physical control of a vehicle) in Montana.

Inferences

If a driver has an alcohol concentration of 0.04 or less, it may be inferred that the driver wasn't under the influence of alcohol.

If the driver has an alcohol concentration of between 0.04 and 0.08, that fact may not give rise to any inference that the driver was or wasn't under the influence of alcohol, but the fact may be considered with other evidence in determining the guilt or innocence of the driver.

If the driver has an alcohol concentration of 0.08 or more, it may be inferred that the driver was under the influence of alcohol. This inference is rebuttable.

What Constitutes a "Vehicle?"

A "vehicle" means any device that can transport people or property down a public highway, except for devices that are moved by animal power or that are used exclusively upon rails or tracks. Under Montana's DUI statute, the term vehicle doesn't include bicycles.

Penalties

First offense: Punishable by imprisonment for between 24 hours and six months, and by a fine of between $300 and $1,000.

Second offense: Punishable by imprisonment for between seven days and one year, and by a fine of between $600 and $1,000.

Third offense: Punishable by imprisonment for between 30 days and one year, and by a fine of between $1,000 and $5,000.

The penalty for a DUI offense is enhanced if there was a passenger in the vehicle who was less than 16 years old at the time of the offense.

Aggravated DUI

While all DUI offenses are treated very seriously in Montana, certain aggravating factors can cause the driver to be convicted of the more serious crime of aggravated driving under the influence. An aggravated DUI offense is committed when one or more of the following circumstances exist:

  • The driver's blood alcohol concentration is 0.16 or greater
  • The driver is under a court order to only operate vehicles with an approved ignition interlock device
  • The person's driver's license is suspended, canceled, or revoked
  • The person refuses to provide a required breath or blood sample and the person's driver's license was suspended, canceled, or revoked within 10 years of the present offense, and/or
  • The person has prior or pending charges for the a violation listed in section 61-8-465(a)(e)

An aggravated DUI offense is punishable by imprisonment for up to one year, and by a fine of $1,000.

What Happens if the Offender is Under 21?

In Montana, it is unlawful for a person who is under the age of 21 to drive (or to be in actual physical control of a vehicle) if they have an alcohol concentration of 0.02 or greater. A first DUI conviction for an offender who is under 21 years old is generally a fine of between $100 and $500. See section 61-8-410 for additional penalties available under this statute.

Implied Consent

Any person who drives a vehicle on a public road in Montana implicitly consents to having their blood or breath tested for the purpose of detecting alcohol or drugs. These tests can be administered by a peace officer who has reasonable grounds to believe that the person has been driving while under the influence of alcohol, drugs, or a combination of both.

Additional Resources

State laws change frequently. For case specific information regarding Montana's DUI laws contact a local DUI lawyer.

Next Steps: Search for a Local Attorney

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