Yes, you can be charged with DUI on private property in Montana, but not on every kind of private property. For alcohol, the statute requires that you drove or were in actual physical control of a vehicle "upon the ways of this state open to the public" (MCA § 61-8-1002(1)(a) and (b)). That phrase includes many privately owned places and excludes others. This page explains where the line has been drawn. It is part of our Montana DUI Guide.
What the Statute Actually Requires
The traffic code defines the phrase: "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)). Two things stand out. The definition says "public or private," so ownership alone is not the test. And it asks two questions about the place: is it adapted and fitted for public travel, and is it in common use by the public?
The same code separately defines a "private road or driveway" as a way in private ownership used for vehicular travel by the owner and those having express or implied permission from the owner, "but not by other persons" (MCA § 61-8-102(21)). The contrast between the two definitions is the heart of most location disputes.
Not Every DUI Offense Has a Location Element
People often hear "DUI only applies on public roads." That is incomplete. The reach of the law depends on which subsection is charged.
| Type of DUI | Where it applies | MCA |
|---|---|---|
| Under the influence of alcohol | Ways of this state open to the public | §§ 61-8-1002(1)(a), 61-8-101(2)(c) |
| Alcohol concentration of 0.08 or more | Ways of this state open to the public | § 61-8-1002(1)(b) |
| Listed drug at or above its blood level | Ways of this state open to the public | § 61-8-1002(1)(f) |
| Under the influence of drugs | Anywhere within this state | § 61-8-101(2)(b) |
| THC of 5 ng/mL or more | Within this state | § 61-8-1002(1)(d) |
| Under 21: 0.02 or any active THC | Within this state | § 61-8-1002(1)(e) |
| Commercial motor vehicle at 0.04 or more | Within this state | § 61-8-1002(1)(c) |
So a person impaired by a drug, or over the THC limit, does not have the same location argument as a person charged with an alcohol DUI. Our page on per se and impairment DUI explains the different subsections.
Parking Lots and Garages
The definition names parking areas, and the Montana Supreme Court has read it generously. In City of Whitefish v. Large, 2003 MT 322, the Court summarized its earlier decisions: a hotel parking garage, a private lot fitted for public travel and in common use, and a privately leased parking space in front of a business all counted. In State v. Krause, 2021 MT 24, the Court applied the phrase to a parking space at a housing complex and said it looks at all of the surrounding circumstances to decide whether it would be reasonable to expect a member of the public to be using the area.
A sign that says "private" or "customers only" does not settle the matter. In State v. Weis, 285 Mont. 41 (1997), the Court described an earlier case involving a bank lot that was posted as private with a tow-away warning and was still a way open to the public, because people going to nearby businesses commonly used it.
Private Lanes, Driveways, and Ranch Roads
Weisitself involved Boulder Lane, a gravel, one-lane road on private easements that led from a county road to three residences. The residents owned and maintained it. The Court held that it was a way open to the public anyway: the lane was fitted for travel, members of the public who were lost, curious, or visiting used it, and nothing impeded or prohibited them. The Court wrote that the law does not limit the phrase to places "legally dedicated to the public use."
There is a limit. In State v. Lapointe, 2025 MT 124, the Court noted that it has given the phrase a broad definition but has also made clear that the alcohol DUI statute "does not apply to drunk driving on private property with limited access." (The Court was discussing the pre-2022 version of the statute, which used the same phrase.) We did not find a decision that draws the exact line for a gated ranch road, a hay field, or a short driveway serving one house. In practice the facts that matter are:
- whether there is a gate, a cattle guard with a closed gate, a locked chain, or posted no-trespassing signs;
- who uses the road day to day: the owner and invited guests only, or delivery drivers, hunters, neighbors, and strangers;
- whether the surface and layout are fitted for ordinary travel;
- whether the road connects public places or dead-ends on private ground.
How You Got There Still Matters
Many private-property arrests are not really about the private property. If an officer finds you in your driveway and the evidence shows you had just driven home on a county road, the State can charge the driving on the road. Proof can come from a witness, a 911 caller, a warm engine, or your own statements. Our pages on being arrested at home after driving and reported drivers cover how those cases are built and where they are weak.
Why the Location Question Is Worth Raising
For an alcohol DUI, the public-way requirement is part of the offense, so the prosecution carries the burden of proving it. The implied consent law uses the same phrase (MCA § 61-8-1016(1)(a)), which means the location can also matter to a refusal suspension. A location argument does not make an arrest go away by itself, and other charges are not limited to public ways. But where the vehicle never left limited-access private land, it is one of the first things a defense lawyer checks, alongside the other DUI defenses.
This page explains Montana law in general as of October 2026, based on the Montana Code Annotated and published Montana Supreme Court opinions. Where we say a question is unsettled, we mean it. It is not legal advice about your specific case.