Yellowstone Park Rules Legal Challenge: Inside United States v. Pulliam and the Fight Over Who Can Make Criminal Law

If you have spent the last week wondering why your feed keeps surfacing stories about a Yellowstone fisherman, a snowmobile-only road, and the U.S. Constitution, you are not alone. A new case out of the U.S. District Court for Wyoming — United States v. Tate Pulliam — has turned a handful of petty park citations into one of the most interesting administrative law fights of 2026.

At its core, the Yellowstone park rules legal challenge is not really about fishing. It is about a question that has been rumbling through the federal courts since the Supreme Court's post-Loper Bright term: who actually gets to make criminal law in the United States? Congress, or a career park superintendent with a compendium of rules and a citation book?

Here is a plain-English breakdown of what is happening, why lawyers across practice areas should care, and what to watch as the case moves forward.

The Facts: A December Fishing Trip That Became a Federal Case

In December 2025, Oregon resident Tate Pulliam traveled to Yellowstone National Park. According to court filings and reporting in Cowboy State Daily, federal officers cited him for three petty offenses:

Fishing in a river that park rules had closed for the winter
Fishing without the appropriate park permit
Driving a standard pickup truck on a road that a park superintendent's order had limited to "over-snow" vehicles such as snowmobiles

Each citation carries criminal penalties. Stacked together, Pulliam reportedly faces up to 18 months in federal prison.

On April 13, 2026, his counsel at the Pacific Legal Foundation (PLF) filed a motion to dismiss in the U.S. District Court for Wyoming. His next hearing is set for May 12, 2026 at the Yellowstone Justice Center, before Magistrate Judge Stephanie Hambrick.

What Pulliam Is Actually Arguing

Pulliam is not arguing that he did not fish, or that he did not drive down the road. He is arguing that none of the underlying rules are valid federal criminal law in the first place. That argument has three distinct pillars, and each one matters well beyond Yellowstone.

1. Nondelegation: Congress Cannot Hand Off the Power to Define Crimes

The motion leans hard on the nondelegation doctrine — the constitutional principle that Congress cannot transfer its core legislative power to the executive branch.

The National Park Service Organic Act authorizes the Secretary of the Interior to issue any regulations he "considers necessary or proper" for park management, and it makes violations of those regulations criminal, punishable by up to six months in prison. PLF argues this is a sweeping, open-ended delegation of criminal lawmaking to a single executive-branch official, which the superintendent then effectively sub-delegates through park-specific compendium rules.

In PLF's framing, quoting Pulliam's counsel Michael Poon: "A park superintendent invented the rules behind these charges, resulting in massive overcriminalization. That is not how lawmaking works under the Constitution."

2. The Appointments Clause: Who Is Allowed to Wield This Power?

Pulliam's second major argument is structural. Under Article II, Section 2 of the Constitution, "Officers of the United States" must be appointed by the president with the Senate's advice and consent; "inferior officers" can be appointed by the president alone, the courts, or department heads, but only if Congress has said so.

Pulliam argues that a park superintendent — able to unilaterally criminalize fishing in a river or driving on a road — is exercising "significant authority" and therefore must be an officer, not a mere employee. Because Yellowstone's superintendent was never appointed through any of the constitutionally permitted paths, PLF says his rules cannot support criminal charges at all.

3. Wrong Statute, Wrong Penalty

The filing also takes a narrower statutory swing: that the government hooked at least one of the fishing citations onto the wrong legal authority. This is a classic defense-lawyer move — even if the larger constitutional arguments fail, a statutory mismatch can knock out individual counts.

Sound Familiar? Meet the Sunseri Prequel

If the arguments sound polished, it is because they are version 2.0.

In 2024, ultrarunner Michelino Sunseri set a record on the Grand Teton, then got hit with a federal criminal charge for running down a "restricted" social trail. PLF raised many of the same nondelegation and Appointments Clause arguments. Magistrate Judge Hambrick — the same judge now hearing Pulliam — rejected them, concluding that a park superintendent is an employee rather than an officer, and pointing to an 11th Circuit decision from 2004 treating Park Service rulemaking as "necessary and proper" to Congress's park-management goals.

Sunseri was convicted at a May 2025 bench trial. His case never reached a merits appeal because President Trump pardoned him in November 2025, leaving the underlying constitutional questions unresolved. PLF is explicitly positioning Pulliam as the vehicle to get those questions decided on the record.

That is why this is worth watching even if the first-round ruling goes the government's way. The roadmap is already built. The only thing needed is a conviction that survives long enough to climb the appellate ladder.

Why This Is a Bigger Deal Than "Fishing Without a Permit"

The Yellowstone park rules legal challenge sits squarely inside the broader post-Loper Bright, post-Jarkesy moment in federal administrative law. If Pulliam's arguments gain real traction — at the district court, at the Tenth Circuit, or eventually at the Supreme Court — the ripples would be substantial.

National Park Service enforcement. Park compendiums regulate everything from drone use to off-trail travel to commercial filming. A successful nondelegation ruling could force Congress to either legislate specific prohibitions or accept that many "violations" are not criminal.
Other land-management agencies. The Forest Service, BLM, Fish and Wildlife Service, and NOAA all operate under similarly broad "necessary and proper" grants of regulatory authority. PLF's NOAA speed-limit challenge is raising parallel issues in the maritime context.
Agency criminal enforcement generally. Any federal regime where an unelected official can define new crimes through rulemaking — environmental regulations, financial compliance rules, import restrictions — becomes a potential target.
Appointments Clause scrutiny of career officials. Expect more defendants to ask whether the career employee who issued a guidance document, ruling, or enforcement decision was constitutionally permitted to do so at all.

This is, in other words, a small case that is designed to do big work.

The Government's Side

It is worth being honest about the counterarguments, because the government has more than a few.

Darin Smith, U.S. Attorney for Wyoming, has publicly said that his office believes Yellowstone Superintendent Cam Sholly acted within his lawful authority, and it is preparing a formal response. The government's playbook will likely include:

Intelligible principle. Under Mistretta v. United States and its progeny, Congress may delegate rulemaking as long as it provides an "intelligible principle" to guide the executive. The Organic Act's conservation-and-enjoyment mandate arguably qualifies.
Mere employees, not officers. Prior courts have treated park superintendents as career employees, not Article II officers, for Appointments Clause purposes. That is exactly what Hambrick held in Sunseri.
Petty offense framing. The charged conduct carries relatively minor penalties. Historically, courts have been more tolerant of administrative rulemaking in petty offense contexts than in felony ones.
Stare decisis and workability. A ruling in Pulliam's favor would upend a century of park-management practice. Courts are often reluctant to embrace that kind of disruption at the trial level.

None of these are slam dunks anymore — that is precisely why PLF is bringing the case — but they are the walls the defense has to push through.

What Lawyers Should Actually Be Watching

Whether you practice criminal defense, administrative law, environmental law, or just keep a casual eye on the regulatory state, there are a few concrete things to track in the coming months.

May 12, 2026 hearing. The first substantive ruling on the motion to dismiss will signal whether Judge Hambrick is rethinking any of her Sunseri-era analysis.
Tenth Circuit posture. If the case goes up, the Tenth Circuit's current appetite for nondelegation and Appointments Clause arguments will shape how aggressively Pulliam can press the constitutional claims.
Parallel cases. Keep an eye on other separation-of-powers challenges to agency criminal enforcement. The more cases that percolate through the circuits, the higher the odds of a Supreme Court cert grant.
Congressional response. If the political branches get nervous about losing park enforcement authority, expect legislative proposals that try to either codify existing rules or narrow the delegation to foreclose these arguments.

For practitioners, the practical takeaway is that "the agency said so" is increasingly a vulnerable foundation for criminal prosecution. Any defense team facing charges rooted in agency rulemaking — not a statute — should at least be evaluating whether a Pulliam-style motion is on the table.

Where LawyerLink Fits In

Cases like United States v. Pulliam are a reminder that modern litigation is rarely a matter of a single statute and a single set of facts. A serious defense strategy now means tracking:

Constitutional theories that are evolving in real time across multiple circuits
Agency guidance documents, compendiums, and rulemaking histories that may themselves be vulnerable
Parallel cases in other districts that can strengthen — or weaken — your motion
Detailed timelines of citations, orders, and communications that support or undercut those theories

LawyerLink is built for firms that need to run that kind of work without losing track of the details. Our platform gives litigators:

Centralized case records so constitutional arguments, statutory analyses, and factual timelines live alongside the matter
Custom fields and task automation to track filings, hearings, and cross-jurisdictional deadlines
Named calendar feeds so multi-attorney teams never miss a motion cutoff or hearing date
Secure client communication with audit trails that hold up under scrutiny

Whether your next filing is a nondelegation challenge or a straightforward criminal defense matter, start with LawyerLink and run the case with the infrastructure it deserves.

Frequently Asked Questions About the Yellowstone Park Rules Legal Challenge

What is United States v. Pulliam about?

It is a federal criminal case in the U.S. District Court for Wyoming in which Oregon resident Tate Pulliam is challenging three Yellowstone National Park citations — two for fishing and one for driving on a road restricted to over-snow vehicles. His motion to dismiss argues that the underlying park rules are unconstitutional because they were created by a career park superintendent rather than by Congress.

Who is representing Tate Pulliam?

Pulliam is represented by the Pacific Legal Foundation, a public-interest law firm that focuses on property rights, separation of powers, and administrative law issues. PLF previously represented trail runner Michelino Sunseri in a similar case out of Grand Teton.

What is the nondelegation doctrine?

The nondelegation doctrine is the constitutional principle that Congress cannot transfer its legislative power to the executive branch. Although the Supreme Court has not struck down a federal statute on nondelegation grounds since 1935, several justices have signaled interest in reviving the doctrine, especially where agencies effectively define criminal conduct.

Could this case really change how national parks operate?

In the short term, probably not. Even a win at the district court level would be limited to Pulliam's specific charges. But if the constitutional arguments are eventually adopted by a federal court of appeals or the Supreme Court, it could force Congress to legislate park rules directly or significantly narrow what superintendents can criminalize on their own.

When is the next hearing in the Pulliam case?

The next hearing is scheduled for May 12, 2026, at the Yellowstone Justice Center, before U.S. Magistrate Judge Stephanie Hambrick.

How does this relate to the Sunseri case?

United States v. Sunseri raised similar nondelegation and Appointments Clause arguments involving Grand Teton National Park. Those arguments were rejected at the trial level, Sunseri was convicted, and President Trump later pardoned him — leaving the constitutional questions unresolved. Pulliam's case is widely seen as a second attempt to get those questions decided on the merits.

Bottom line: A pair of fishing citations and a road-closure ticket have become a live test of one of the most contested questions in modern constitutional law — whether career federal officials can define what counts as a federal crime. However Judge Hambrick rules on May 12, United States v. Pulliam is likely to echo far beyond the boundaries of Yellowstone National Park.