Montana DUI Guide

Sleeping in Your Car and Actual Physical Control in Montana

Montana's DUI statute covers a person who drives or is in actual physical control of a vehicle. The second half reaches people who never left the parking lot.

Written by

Misty Gaubatz, Partner, A&M Law

Licensed Montana attorney and co-founder of A&M Law. Over two decades in the practice of law focusing on family law, criminal defense, and DUI defense, with federal and state court experience and a Certificate in Mediation.

Montana Bar #122346+ years as an attorney, with over two decades working in the lawReviewed by Ashley HurlbertLast reviewed: October 1, 2026

One of the most common reactions to a DUI charge is "but I wasn't driving." In Montana that is not the end of the matter. The statute applies to a person who "drives or is in actual physical control of" a vehicle while under the influence (MCA § 61-8-1002(1)). This page explains what the second phrase means and how courts decide it. It is part of our Montana DUI Guide.

There Is No Statutory Definition

Montana's DUI definitions do not define "actual physical control." The meaning comes from decisions of the Montana Supreme Court. The Court has described the purpose of the phrase as preventing DUI at its inception: the law does not wait for an impaired person to put the vehicle in motion.

The Test: Totality of the Circumstances

The leading case is State v. Sommers, 2014 MT 315. The Court held that the fact finder "should consider the totality of the circumstances rather than focusing only upon the circumstances of the vehicle and the defendant at the time they are discovered." It listed factors a jury may consider:

where in the vehicle the person was located;
whether the ignition key was in the vehicle, and where the key was located;
whether the engine was running;
where the vehicle was parked and how it got there;
whether the vehicle was disabled: broken down, mechanically inoperable, stuck, or otherwise immovable;
how easily the person could have cured the vehicle's disability.

The Court said the list is not all-inclusive, that no single factor necessarily decides the question, and that it is up to the jury to decide what weight each one gets.

The Court also offered a working definition: a person is in actual physical control when the person is not a passenger and is in a position to cause the vehicle to move, or to control its movement in some manner or direction. Under that language, a person "need not be conscious" to be in actual physical control. More recent decisions in 2024 apply the same test.

What the Cases Show

Asleep in the driver's seat, engine running. Conviction affirmed, even though the defendant said he was only sleeping it off. Intent to drive is not an element (State v. Hudson, 2005 MT 142).
A vehicle that cannot move. Relevant, and a jury must be allowed to consider it (Sommers).
How the vehicle got there. Where the circumstances show the person drove it to that spot while intoxicated, a jury may infer the person exercised control in getting it there (Sommers).

So the two things people believe, that keys out of the ignition is always safe and that sleeping in a car is always a DUI, are both wrong. It is a fact question, and that is why these cases are defensible.

Where It Applies: Parking Lots and Private Roads

An alcohol-based DUI must occur "upon the ways of this state open to the public." That phrase is defined broadly: "any highway, road, alley, lane, parking area, or other public or private place adapted and fitted for public travel that is in common use by the public" (MCA § 61-8-102(29)). In State v. Krause, 2021 MT 24, the Supreme Court applied it to a parking space at a housing complex, looking at whether it would be reasonable to expect a member of the public to be using the area.

A bar parking lot, a grocery store lot, and a gas station all fit that description. Several other provisions do not have a public-way requirement at all: the THC limit, the under-21 offense, and the commercial vehicle limit apply "within this state," and the provisions on driving under the influence of drugs apply anywhere within the state (MCA §§ 61-8-1002(1), 61-8-101(2)).

How These Cases Are Defended

Because the test is a list of facts, the defense is built from facts:

exactly where the person was, and whether that was documented on video or only in a report;
where the keys were found, and by whom;
whether the engine was on, and if so why, such as heat on a winter night;
whether the vehicle could actually have moved;
what evidence, if any, shows who drove the vehicle there and when;
whether the location was a way open to the public;
whether the officer had a lawful basis to make contact and to arrest.

The rest of the case is the same as any DUI: the field sobriety tests, the breath or blood result, and the license consequences of a refusal.

This page explains Montana law in general as of October 2026, based on the Montana Code Annotated and published Montana Supreme Court opinions. It is not legal advice about your specific case.

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FAQ

Sleeping in Your Car and Actual Physical Control in Montana FAQ

Can you get a DUI for sleeping in your car in Montana?

Yes. The Montana Supreme Court has upheld DUI convictions of people found asleep in a vehicle. In State v. Hudson, 2005 MT 142, the defendant was asleep in the driver's seat with the motor running and said he was sleeping it off; the conviction was affirmed. Whether a particular person was in actual physical control is decided on all the circumstances.

Is it a DUI if the keys are not in the ignition?

Not automatically either way. Where the key was is one of the factors a jury considers under State v. Sommers, along with where you were sitting, whether the engine was running, where the vehicle was parked and how it got there, and whether it could move. No single factor decides the question.

Does it matter that I was not going to drive?

Not as a defense in itself. DUI is an absolute liability offense in Montana (MCA § 61-8-1002(5)), and the Supreme Court has declined to add an intent element (State v. Hudson). What matters is whether you were in a position to control the vehicle, not what you planned.

What if the car would not start or was stuck?

That matters. In State v. Sommers the Supreme Court held that a vehicle's ability to move is relevant, and that it was error to tell a jury it does not matter that the vehicle is incapable of movement. The jury may consider whether the vehicle was disabled and how easily the person could have fixed that.

Can I be charged with DUI in a parking lot or on private property?

Often, yes. An alcohol DUI must occur on the "ways of this state open to the public," and that phrase includes any highway, road, alley, lane, parking area, or other public or private place adapted and fitted for public travel that is in common use by the public (MCA § 61-8-102(29)). The Supreme Court has applied it to private parking lots. Drug-based provisions apply anywhere within the state (MCA § 61-8-101(2)).

What is the safest thing to do if I have been drinking and my car is right there?

Do not get into the driver's seat. Arrange a ride or go back inside. If a vehicle is the only shelter, the law offers no guaranteed safe way to wait in it, because the question is decided afterward on all the circumstances. This is general information, not a recommendation for any particular situation.

Charged Without Driving?

Physical-control cases depend on details: the keys, the seat, the engine, the location. Call 406-830-3060 for a confidential consultation.

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