Montana Code Annotated, Section 61-8-401
Type of DUID Law: Under the influence: Impairment
(1) It is unlawful and punishable as provided in 61-8-442 and 61-8-731 through 61-8-734 for any person who is under the influence of : …
(b) a dangerous drug to drive or be in actual physical control of a vehicle within this state;
(c) any other drug to drive or be in actual physical control of a vehicle within this state; or
(d) alcohol and any dangerous or other drug to drive or be in actual physical control of a vehicle within this state. …
(3)(a) “Under the influence” means that as a result of taking into the body alcohol, drugs, or any combination of alcohol and drugs, a person’s ability to safely operate a vehicle has been diminished.
Type of Drugs Prohibited: Any drug or any dangerous drug
Marijuana use in vehicle
- Montana allows the medicinal use of marijuana by certain registered patients. An LEO who has “reasonable cause to believe” that a person with a valid registry identification card is driving under the influence of marijuana may apply for a search warrant to require the person to provide a sample of the person’s blood for testing. MCA 50-46- 320(7)(a). Any registered cardholder who is found guilty of a drugged driving violation faces the revocation of their registry card.