After mountain runner Michelino Sunseri’s legal travails ended with a presidential pardon, a conservative legal group is rehashing some of its constitutional arguments from that case — and again setting its sights on the National Park Service’s ability to make criminal laws.
“The defenses here are very similar,” said Michael Poon, a Pacific Legal Foundation attorney.
The Pacific Legal Foundation, based in California, represented Sunseri and has challenged Jackson and Teton County’s housing mitigation fees. The law firm fights perceived government overreach and has a new client whose case is tied to the Greater Yellowstone Ecosystem: Tate Pulliam from Bend, Oregon.
Yellowstone National Park charged Pulliam in December 2025 with petty offenses for fishing without a license, illegally fishing in a river that was closed for the winter (it’s not clear which), and driving his pickup truck down a road that was only open to over-snow vehicles, like snowmobiles, according to court records and the foundation’s website.
Foundation lawyers moved to dismiss the case. Assistant U.S. Attorney Ariel Calmes has not yet filed a motion in response.
In representing Pulliam, the Pacific Legal Foundation attorneys are teeing up arguments about the power of executive agencies that are nearly identical to those they made in Sunseri’s defense.
One argument targets part of the 1916 law that established the park system, the National Park Service Organic Act. Specifically, the Pacific Legal Foundation argues that the Organic Act unconstitutionally delegated regulatory authority to the park service. The group’s attorneys say Congress is the only branch of federal government with the authority to pass laws, an argument that falls under a legal doctrine known as “non-delegation.”
Some legal experts question whether a judge will back the foundation’s interpretation of that doctrine.
“The non-delegation argument attacks the constitutionality of the Organic Act,” said Poon, the Pacific Legal Foundation attorney. “The way the Organic Act gives away Congress’ criminal law making authority is itself unlawful.”
The principles of non-delegation are broad and hotly debated. They come from Article I of the U.S. Constitution, which gives “legislative powers” to Congress.
Cases about the doctrine have reached the U.S. Supreme Court and touch on everything from the Federal Communications Commission’s regulation of radio, TV and cable to President Donald Trump’s ability to impose tariffs, according to Alan Morrison, a law professor at George Washington University who has argued 20 cases before the Supreme Court.
But in Yellowstone and Grand Teton National Park, the Pacific Legal Foundation has raised the argument around smaller issues, like the park service’s ability to regulate switchback cutting, fishing and where people can and can’t drive.
Morrison questions whether a judge will back the Legal Foundation’s arguments, which raise questions about how the highbrow legal argument would be applied in practice. As an example, he pointed to speed limits.
“Imagine what would happen if the Congress, which can hardly do what it’s doing now, had to set the speed limit at every national park in the country,” Morrison said. “That’s the kind of practical problem you’re coming up with.”
John D. Leshy, an environmental lawyer who specializes in public lands and served as the Department of the Interior’s general counsel during former President Bill Clinton’s administration, is also skeptical of the foundation’s non-delegation argument. In an email, he said that a century of federal court decisions, including some from the Supreme Court, have upheld Congress’ delegation of authority to land management agencies, like the park service, U.S. Forest Service and Bureau of Land Management.
“PLF is asking the courts to scrap all that precedent,” Leshy wrote. “Doing so would put appointed, life-tenure judges — rather than executive branch officials who are accountable to the chief executive that we elect — in charge of what happens on the public lands. That, in my view, is a very bad result that can only lead to mischief and uncertainty.”
Poon is joined in defending Pulliam by two other Legal Foundation attorneys: Allison Daniel and Damien Schiff, a high-profile litigator who argued the landmark Sackett v. Environmental Protection Agency case before the U.S. Supreme Court. Schiff succeeded and drastically narrowed the definition of “waters of the United States,” limiting what wetlands are eligible for protection under the Clean Water Act. The decision was heralded by farmers and industry groups, but lambasted by environmental organizations.
Pulliam is also represented by Eric Goldwarg, a Bozeman, Montana, attorney.
As the Pacific Legal Foundation defended Sunseri, Jefferson Powell, a constitutional law expert at Duke University and former Department of Justice attorney, said it appeared the group was trying to set up a “test case.” That’s a lawsuit brought to clarify an unclear legal point or advance a particular view of the Constitution. Sackett was one such case.
Poon, however, says that’s not what’s happening here.
“When we take on a case and we represent a client, the client’s interests always come first,” he said. “That means demonstrating to the courts that the government acted unlawfully here and should never have charged Tate.”
Poon said the goal is not necessarily bringing the case to the Supreme Court.
“We are hoping and aiming to win this case at the lower level,” he said.
