Perspectives
March 13, 2026 | By Richard Moore
Policy Issues
Constitution Environment

State’s Public Trust Doctrine Shouldn’t be Trusted

It’s time to revisit a mantra that has grown far beyond its constitutional foundation.

Is that driftwood, or drifting doctrine?

For more than a century, as one writer has put it, Wisconsin’s public trust doctrine has been celebrated as the gold standard of environmental law.

Hate to break the news, but what they should call it is constitutional camouflage. Look inside the vault, and what we find is almost all fool’s gold. What began as a simple guarantee that Wisconsin’s navigable waters would remain public highways forever free—the real treasure—has morphed into a highly expansive and ideological doctrine for regulating land, expanding state power, and shrinking property rights.

Oh sure, environmental advocates love the “Public Trust Doctrine.” They always make sure to capitalize the deity. It sounds so healthy that environmentalists wrap their hummus and avocados in it. Law professors write admiring “scholarly” articles about it. News anchors perseverate at the mere prospect of mentioning those three magical words.

Not least, the state’s regulatory carpenters use it as a hammer to expand state control over land and water, and to declare your property nonconforming. Beneath all this nobleness, though, lies an uncomfortable question: Have any of these people ever read the state constitution, at least as it pertains to the public trust doctrine?

That’s what I thought.

For starters, the constitution never mentions a public trust doctrine. Said doctrine, such as it is today, bears little resemblance to the narrow constitutional text from which it supposedly comes. Birthed as a skinny sentence, it must now wear fat-man pants just to get through a courthouse door. And the courthouse is precisely where the doctrine went on a binge-eating tear, for its transformation did not happen through constitutional amendment or legislative debate but almost entirely through activist judicial expansion.

Writing in SSRN Electronic Journal in 2016, in “A Doctrine Adrift: Wisconsin’s Public Trust,” attorney Nicholas Bullard bluntly concluded that the current iteration of the doctrine was fundamentally unconstitutional.

“And, it is not even a close call,” Bullard wrote. “Contrary to some suggestions, Wisconsin’s trust is not based on ancient law or ownership of submerged land. It is grounded in a provision in the state constitution. Yet bizarrely, the Wisconsin Supreme Court has never subjected that provision to standard constitutional interpretation.”

Instead, Bullard wrote, the court has ignored the constitutional text and expanded the doctrine at will: “After 160 years of growth, the state’s public trust is now vast and potent. It is also detached from its constitutional moorings.”

Bullard was right, as I have long asserted, and with another potential public trust doctrine case working its way through the courts—a lawsuit in Shorewood involving a trespass violation for walking a dry beach—and a radical Supreme Court no doubt drooling over the possibility of taking up the matter, Wisconsin could see the doctrine expanded once again.

That said, the state’s public trust doctrine should be reviewed, not to expand it but to cut its sails and to cabin it back within its own jurisdiction. At the very least, the fantastical use of the doctrine to protect so-called natural scenic beauty should be jettisoned once and for all.

What the constitution says

Spoiler alert: The state constitution says far less than the courts now claim. Oh, there are a lot of hoots and hollers about its royal foundations, mutterings about Roman Law and English common law (the latter of which is true, sort of, coming as it does from the Northwest Ordinance of 1787 and its bedrock of British principles).

Even so, the doctrine’s legal foundation is less regal than one might imagine. One might even describe it as a ‘No Kings’ concept. It rests on a single sentence in the Wisconsin Constitution, Article IX, Section 1:

“[T]he river Mississippi and the navigable waters leading into the Mississippi and St. Lawrence, and the carrying places between the same, shall be common highways and forever free, as well as to the inhabitants of the state as to the citizens of the United States, without any tax, impost or duty therefor.”

It is pedestrian and populist in intention, and textually exact. Not a word about wetland protection or water quality. Not a word about recreation. Not a word about natural scenic beauty or impervious surfaces or those shoreland cottages and boathouses that progressives like to call eyesores. More important, there’s no interpretive hint of any of those things.

The text is explicitly about navigation, and about unobstructed and untaxed use, pure and simple. Back in the day, when the Northwest Ordinance was crafted, the recognized intent was to prevent obstruction—physical or fiscal—of commercial waterways. Early Wisconsin courts understood this. They knew that the doctrine existed to protect the public’s ability to use navigable waters as transportation routes, and early public trust cases focused almost entirely on preventing physical obstructions to navigation: The courts blocked bridges, mills, dams, and other obstructions to navigation.

Everyone also understood that the doctrine applied only to those navigable waters themselves—the use of the water, not to surrounding lands and not to access of the waters, which the DNR acknowledges even to this day: “Navigable streams are public waters. Because navigable waters are public, they may be used for fishing, provided public access is available, or you have the permission of the landowner to cross their property to reach the water.”

But that narrow interpretation did not remain narrow for long. Over time, Wisconsin courts gradually transformed the doctrine into something much larger than a rule about navigation. They added ever more uses, eventually going so far as to grant the right to natural scenic beauty, which, of course, only the DNR could define. Today, the doctrine is invoked to justify the regulation of nearly every aspect of rural waterfront development.

To accomplish all this, generations of judges and justices have had to mutilate the constitution, attaching their own amendments to it. The definition of navigable waters, for instance, expanded dramatically. Originally, the term referred to waterways capable of serving as commercial transportation routes. Over time, the courts adopted a far looser “navigable in fact” test, under which even small streams capable of floating a canoe at certain times of the year could qualify as navigable. The doctrine expanded geographically, too, suddenly covering not just navigable waters leading into the Mississippi and St. Lawrence, and the carrying places between the same, but every navigable water in the state, including artificial bodies of water.

But here is the key constitutional problem. None of those expansions appear in the text of the Wisconsin constitution. They were created by judicial magic as well as by statutory construction and codification of the courts’ hocus-pocus, virtually all of it taking communion at the altar of the public trust doctrine.

The problem is, the doctrine in its mangled form cannot survive originalist scrutiny. Under that test, if the Constitution says navigable waters are “common highways,” we must ask: what did people in 1848 understand that phrase to mean? As noted, most certainly they meant transportation, commerce, and navigation, not wetland policy or large lot zoning. If society wants new policies, the legislature should pass them, or voters should amend the constitution.

This interpretation can’t pass textual scrutiny, either: Liberal judges might wish with all their bleeding hearts that natural scenic beauty was in the constitution, but the words just aren’t there, and the thought wasn’t even a gleam in the authors’ eyes.

And that’s not all, folks

Actually, there’s a lot bigger problem with the public trust doctrine than the flaws so well pointed out by Bullard and others. This problem, if ever properly adjudicated, could become the Armageddon of public trust fattery. Let’s take a look.

Right now, the doctrine shapes vast areas of land-use policy and is used to justify a wide array of regulatory policies, from shoreland zoning to wetland protection, from restrictions on waterfront development to limits on docks and piers. In pursuing those restrictions, the Department of Natural Resources has long insisted that the doctrine requires strict limits on development near navigable water bodies and that easily implementable, up-to-date minimum standards are critical to protecting Wisconsin lakes and streams.

What DNR officials never emphasize is that today, and ever since shoreland zoning was enacted, its administrative regulations in NR115 apply to only a portion of the state’s shorelands—generally, with a couple of exceptions, those found in unincorporated regions of the state.

And that’s a big problem. For one thing, the issue implicates equal protection and the validity of state statutes that impose strict development standards on property owners in unincorporated towns but permit those in more densely populated cities and villages to build at will.

But there’s another constitutional implication: By explicitly preventing the DNR from protecting all the waters of the state, those exemptions for incorporated cities and villages effectively compel the agency to violate its public trust responsibilities under the state constitution.

In articulating the purpose of existing water quality statutes, lawmakers clearly recognized that constitutional responsibility. For instance, the ‘statement of policy’ section of Chapter 281, the state’s water resources law, commands the DNR to develop an all-inclusive plan of action to safeguard the state’s waters: “Continued pollution of the waters of the state has aroused widespread public concern. It endangers public health and threatens the general welfare,” the statute states.

Thus, the statute continues, its purpose is “to grant necessary powers and to organize a comprehensive program under a single state agency for the enhancement of the quality management and protection of all waters of the state, ground and surface, public and private.”

To accomplish those goals, Chapter 281 establishes a “shorelands” zoning district composed generally of all “lands under, abutting or lying close to navigable waters,” and, precisely, of the area within 1,000 feet of the ordinary high-water mark of navigable lakes, ponds, and flowages and within 300 feet of navigable rivers and streams and to the landward side of flood plains.

Notably, the statutory definition of shorelands does not exclude incorporated municipalities; thus, the shoreland district encompasses cities, villages, and towns. In addition, the statement of purpose clearly called for a comprehensive program targeting all sources of municipal pollution, not just sources of unincorporated municipal pollution.

The chapter cites the public trust doctrine in its statement and purpose section, and so the defining language of the statutes was not just a legislative wish; it was a constitutional mandate.

It was a mission the courts had long embraced, culminating in 1966 in Hixon v. PSC, in which the Supreme Court declared the cumulative impacts of development near navigable waters to be a valid concern under the public trust doctrine, and said the state must consider the cumulative ramifications of allowing a given practice on a statewide basis.

The Legislature’s adoption of shoreland regulations was a direct response to those court directives and interpretations.

Still, politics will be politics, and, when the Legislature got around to ordering the DNR to craft shoreland regulations to satisfy its public trust obligations, most cities and villages got magically omitted from the equation, and that omission has arguably accomplished exactly the opposite of the law’s stated intention, that is, it prohibits the agency from protecting water quality in a significant portion of the state.

To be sure, the DNR, by its own words, has pushed revisions to NR115 and the application of rigorous new regulations to ever-farther reaches of land precisely because the agency says those edicts are vital in shoreland areas to protect water quality and fish and wildlife habitat. If those minimum standards are necessary for the agency to meet the statutory objectives of a comprehensive program to protect all the waters of the state—the Chapter 281 requirement —then logic would dictate that the absence of those minimum measures in nearly 200 cities and in more than 400 villages across the state means the program is not comprehensive and thus does not meet the statutory objective.

Indeed, the Supreme Court’s liberal majority ruled that the public trust doctrine, not just statutory police powers, enables the DNR to regulate pollution no matter where it occurs. That decision in Clean Wisconsin v DNR

allows the DNR to regulate high-capacity wells. Here’s how justice Rebecca Dallet wrote it for the majority:

“We unanimously rejected those arguments, holding that the DNR has both a constitutional duty and the statutory authority to consider the environmental effects of all proposed high-capacity wells. We held that the DNR’s constitutional public-trust duty stems from the legislature delegating to the DNR that obligation via Wis. Stat. §§ 281.11 and 281.12. And for the DNR to fulfill its duty under § 281.11 to “protect, maintain, and improve” the state’s water supply, it had to consider the environmental effects of a proposed high-capacity well. Put another way, a permit application for a high-capacity well triggers the DNR to act on its public-trust duty, under which it cannot ignore ‘concrete, scientific evidence of potential harm to waters of the state.’”

The same argument can be made about incorporated areas. Under the public trust doctrine, the DNR, to use the language of that court, has both a constitutional duty and the statutory authority to consider the environmental effects of all shoreland development statewide. For the DNR to fulfill its constitutional duty under § 281.11 to “protect, maintain, and improve” the state’s water quality, it must consider the environmental effects of shoreland development in incorporated areas. Such development must trigger the DNR to act on its public-trust duty, under which it cannot ignore “concrete, scientific evidence of potential harm to waters of the state.”

One can take this line of reasoning one step further, namely, that the lack of minimum regulations in older cities and villages in effect debars the DNR from protecting water quality even in unincorporated areas, despite the applicability of NR115 in those locations, because lines of incorporation cannot stop water from flowing between the city and the countryside. Because all watershed systems are so intricately connected, allowing ongoing runoff and pollution in the state’s cities and villages inevitably transforms and degrades the vast majority of water bodies in the state, thereby subverting the very intent of the regulations in unincorporated areas.

What’s more, the statutes governing incorporated areas explicitly allow the improvement of shorelines, with far more lenient impervious surface regulations for some of the most polluted areas of the state. That absolutely contradicts official DNR science—and shoreland regulations—which demands 75-foot setbacks, limited impervious surfaces, and thick vegetative buffers of at least 35 feet. Indeed, as I shall document in upcoming research, the amount of connected impervious surface in a watershed remains the best measure for predicting fish density, species richness, diversity, and other indicators of water quality.

The question is, are such exemptions and indeed programs that encourage waterfront development compatible with Chapter 281? If they are not, they are violative of the state’s constitutional requirements under current interpretation of the doctrine.

On the other hand, if such exemptions and waterfront development are compatible with a comprehensive program designed to protect water quality, then why does the state insist it is necessary to proscribe such development in unincorporated territories?

The state should not be able to have it both ways. Either the public trust doctrine can leap from ship to shore and from water to dry beach to wetland, or it can’t, and its scope is limited. Either today’s engorged and bloated doctrine, waddling around rural areas in its fat man pants, must be able to also eat its way through the state’s cities and villages, or its jurisdiction must be appropriately limited.

The point is not to halt development in cities and villages; it is to stop the extreme and discriminatory application of an unconstitutional doctrine to unincorporated areas of the state and to those property owners, for no good reason other than land confiscation for the state. The public trust doctrine needs to stay in its lane. Of course, the DNR has encountered this argument before and responded that cities and villages frequently operate under separate zoning systems, already have stormwater controls, sewer systems, and local zoning ordinances that mitigate pollution in ways rural areas do not.

That argument fails because those methods of pollution abatement have failed. Over the years, water quality in urban watersheds has steadily deteriorated, at best not improved, and has been degraded beyond acceptable standards. Indeed, the small number of watersheds whose impervious surface levels have reached a threatening critical mass lie mostly in incorporated congested and industrial areas of the state, and environmentalists’ own reports don’t show much improvement over the years.

It is the DNR’s public trust responsibility to address it. Or, to say it another way, while the DNR constantly touts the new technologies available to protect water quality in rural areas, it still hasn’t figured out how to apply even its old science to cities and villages.

Back in 2010, that most radical of radicals, then DNR water-quality chief Todd Ambs, actually admitted in an email to then state Senator Jim Holperin (D-Eagle River) that cities and villages should not be exempt from shoreland zoning. Holperin had been questioning the different standards for NR115:

“Or, better yet, will you join me in applying the rule everywhere, including incorporated areas?” he asked Ambs. “Why should Madison be exempt, exactly?”

In Ambs’s view, Madison and other incorporated areas should not be exempt. The legal exemption for incorporated areas didn’t add up to him, he wrote, and he told Holperin it would be a pleasure to discuss overturning it.

“Exactly the discussion I would be happy to have,” Ambs replied to Holperin. “I would love to see the rule applied everywhere. Exempting the cities never made sense.”

So there you go. Eventually, the DNR wants the urban areas, too. It’s just that they think rural Wisconsin is an easier target at first.

But the truth holds. If we are going to maintain current interpretations of the doctrine, or expand them in cases like Shorewood, then the doctrine must be applied everywhere, including cities and villages.

Of course, there is a way out of this that should make everybody happy. I’ve written about it before, as have others, including justice David Prosser in the Lake Koshkonong decision and Bullard in his paper. It entails scaling back the public trust doctrine to protect only recreation, travel, and commerce on truly navigable waters.

No scenic beauty. No application of the doctrine above the OHWM. No exemptions for cities and villages.

That would not mean—though environmentalists would howl from the rafters—that the state can’t regulate water quality, erosion, and habitat, including establishing distinctions between urban and rural areas.

It can, it just has to use its statutory police powers, which are rooted in democratically employed and controlled regulations rather than in the righteous rights and sweeping edicts of the constitution. States have always possessed broad police power to regulate land use and protect public health, safety, and welfare. Pollution control laws, zoning, stormwater regulations, wetland protections, and shoreline setbacks can all rest comfortably on the police power.

Using statutory authority, the state can regulate urban and rural areas differently. Zoning law does this all the time. Ironically, narrowing the public trust doctrine could actually strengthen environmental regulation by grounding it in clearer statutory authority. It also avoids the awkward situation in which the state claims the doctrine is so powerful that it requires regulating rural shorelands but is somehow not powerful enough to regulate cities.

The sad truth is that Wisconsin’s legal system currently uses the public trust doctrine as a shortcut around democratic policymaking. Instead of legislatures and local governments openly debating and deciding how much shoreline regulation is appropriate, courts and agencies invoke the trust as if it answers every question.

Just not in Democratic run cities.

The state cannot continue to treat the public trust doctrine as a sweeping constitutional command when regulating rural shorelands and as a suggestion when it comes to incorporated areas; that contradiction exposes the current doctrine’s ideological imperialism and demands limits the courts have long refused to impose.

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