DUI in Yellowstone or Grand Teton National Park.

The stop

The Grand Teton cases come off U.S. 26/89/191 after dark: the drive back to Jackson from dinner at Signal Mountain or Jackson Lake Lodge, the commute home from a job at Colter Bay, the last stretch to the airport before an early flight. In Yellowstone it is the Grand Loop Road between the junctions, the exits from the Madison and Grant Village campgrounds, and the road out to Gardiner at the end of an evening. Both parks also see the driver who never left the parking lot, asleep in a running car at a trailhead, which is "actual physical control."

What follows is closer to a city DUI arrest than to a park ticket: roadside exercises, a portable breath device, then handcuffs, a tow, and a booking rather than a notice handed through the window. From the initial appearance on, the case proceeds like every other petty offense in the district, with one difference: the court's pay-by-mail schedule lists §§ 4.23(a)(1), (a)(2), and (c)(2) as mandatory-appearance offenses. No amount ends a park DUI by mail. The page on the notice explains the boxes; for a DUI the box is always A. Drugs are charged under the same paragraph: "a drug, or drugs, or any combination" includes marijuana bought lawfully in Montana, a sleeping pill taken at the lodge, and a prescription carried for years, and paragraph (b) says the prescription is not a defense to driving impaired by it. Possession of the marijuana itself is a separate charge, and the page on marijuana and drug charges covers it.

The number

A ranger's observations, the roadside exercises, and a breath result under the limit can all be offered to prove impairment, and the regulation says a result below 0.08 creates no presumption either way. The per se paragraph adds that if the state's own drunk-driving law sets a stricter limit, the stricter limit governs. Wyoming's adult limit is also 0.08, so for most drivers the two match; Wyoming's separate 0.02 rule for drivers under twenty-one is a question I would want to look at before assuming it stops at the park boundary. Refusing does not keep the number out of the case: the regulation allows blood by warrant, the court issues them, and a driver who then resists the warrant has moved from a petty offense into contempt. In one Grand Teton case announced in 2024, the contempt count alone drew ten days, on top of seven for the refusal.

Probation and the park ban

Probation in these cases is unsupervised and short, one to three years in the announced DUI sentences, and it usually carries a condition that the defendant not enter the park while it runs. For a visitor, that is a footnote. For someone who lives in Jackson, Wilson, or Gardiner, it is the term that changes daily life, and it is negotiable in a way the statutory driving ban is not. For someone who lives in this valley, the driving ban is the highway to the airport, the road to Moran and to Yellowstone, and every lodge and marina north of Moose, closed for a year.

Your license at home

A federal magistrate judge does not suspend a state driver's license; no federal court has that power, and there is no federal administrative suspension of the kind Wyoming imposes in its own DUI cases. What happens to your license is decided at home, and it depends on whether the conviction reaches your state and what your state does with it. A park DUI cannot be paid by mail, so the paid-notice rule that keeps a speeding forfeiture off your state record does not arise; a DUI conviction entered in open court is one the federal court's 2026 rule allows it to report to your state, and whether and how that happens is a question I confirm in each case rather than assume. Once a report arrives, states act under their own statutes and, for most of them, under the Driver License Compact, which treats an out-of-state DUI conviction as though the conduct had happened at home. Wyoming's statute directs a ninety-day suspension on a first conviction "under W.S. 31-5-233 or other law prohibiting driving while under the influence" (W.S. § 31-7-128(b)), language broad enough to include a federal regulation.

The border, and a commercial license

Canada treats a conviction for driving while impaired by alcohol or drugs, for an offense committed on or after December 18, 2018, as serious criminality for purposes of admission, and a person with such a conviction may be refused entry until rehabilitation or a temporary resident permit is obtained. That applies to an American with a Yellowstone conviction driving north to Banff the following summer. The page for visa holders covers the Canadian visitor cited here, and the immigration statute generally.

Commercial drivers have the least room. The federal disqualification table removes a CDL holder's commercial privileges for one year on a first conviction for driving under the influence of alcohol in a non-commercial vehicle, meaning the family car on vacation, and for a first refusal of an alcohol test under an implied-consent law (49 CFR § 383.51, Table 1). Whether a licensing state applies that table to a federal park conviction is a question for that state and the employer; the page on records covers the reporting duty and the other checks a conviction meets. For a professional driver the disposition is a livelihood question, and I treat it as one.

A park DUI and a Wyoming DUI are different cases

A driver stopped on Broadway in Jackson is charged under W.S. § 31-5-233, prosecuted by the county attorney in Teton County Circuit Court, entitled to a jury, exposed to up to six months and $750 on a first offense, and, separately, to a ninety-day administrative suspension imposed by the Department of Transportation under the state implied-consent law before the case is decided. A driver stopped a few miles north on the same highway, past the park boundary, answers to a federal regulation and an Assistant U.S. Attorney, is tried to a magistrate judge without a jury, faces six months and $5,000, and is subject to the statutory driving ban instead of a state suspension. The federal case has no administrative hearing, but it produces a federal record that no expungement law reaches. I handle both from the same office; the page on Wyoming DUI defense is the one to read if your stop was in town.