Policing the Police Power

April 8, 2025

By Anthony Sanders

Good Governing: The Police Power in the American States, by Daniel B. Rodriguez. Cambridge University Press, 354 pages, $39.99.

Any attorney litigating a constitutional challenge to a state statute is going to see two words in the government lawyer’s brief: “police power.” In my years as a public interest attorney, I lost count of how many adjectives counsel conjoined to that term. “Vast,” “sweeping,” and “plenary” were common. Yes, these advocates will begrudgingly admit that there are certain constitutional limits—called “rights”—to the state’s power to legislate for public health, safety, welfare, and (even) morals. But they’ll insist those are small outposts amid the police power steppe.

Luckily, courts don’t always agree with how small the state’s attorney thinks those rights-outposts are. But today’s judges do buy the underlying proposition: That the police power allows the state to do anything, minus rights. A new book reminds us that was not always the case. Earlier in the Republic’s history the police power itself had limits. Whether we can get back to that is a different story, as is the question of who polices the police power.

Northwestern law professor Daniel Rodriguez tackles these questions, and more, in Good Governing: The Police Power in the American States. As the title should remind you, the federal government does not have a basic, almost organic, power to regulate. It is a government that still only (even if just technically) possess limited, enumerated, powers. American states are different. State constitutions do not need to enumerate all the powers of their legislatures. As Rodriguez reminds us, even at the Founding “state constitutions were documents of limit, not grant.” Nevertheless, while not precisely defined, the police power is a creation of those constitutions. No constitution, no Lockean delegation of power to the state, and thus no police power.

Undefined and unenumerated

Yet, to both constitutional theorists and lawyers, this paradox raises more questions than answers. Which is perhaps why the police power has always had a bit of mystery to it—constitutionally created yet undefined and unenumerated. Rodriguez outlines this internal tension and how it shaped the police power’s evolution in the Republic’s early years. While those crafting state governments held the small-r republican view that “the fundamental function and obligation of the government [was] to protect and promote the public welfare,” they also believed there needed to be “sufficient checks and balances to limit power.” Much of the latter concerned how to protect private property. Some of these limits manifested themselves in the courts, and in judges rejecting certain actions as beyond the police power. But, Rodriguez argues, most of it was structural, such as taking power away from the executive and placing it with the legislature, or, as fears and fashions changed, vice versa.

Rodriguez has done us all a great service in putting the story and the hopes and concerns surrounding the police power in one place. His scope and analysis are sweeping—often bracingly so. Perhaps that is unavoidable in a subject this large—a subject that essentially touches on all of modern administration and regulation. Classical liberals will find the book useful to learn both the long persistence of the belief that it is the government’s job to regulate for the public welfare—a story which may surprise and disappoint some of them—and how their suspicions that the police power is not what it used to be are in many ways accurate. Further, from the book they can better see where the “pressure points” are in the police power today.

Policing—and pushing—a bigger state

Governments of all complex societies (that we know of) have always regulated beyond Robert Nozick’s night watchman state. Drawing approvingly from historians of republicanism such as Gordon Wood, Rodriguez argues that early “state constitutions reflected an active, public-spirited conception of governing, one that echoed Whiggish political theory.” States and cities did indeed have a myriad of regulations at this early stage, including inspection and quarantine ordinances, fire codes, and, of course, blue laws. But Rodriguez is careful not to go as far as others—most prominently, William Novak—have gone to imply that the early Republic was just as awash with restrictions on liberty (for white males, at least) as we are today (although he does cite Novak approvingly at times). He emphasizes that respect for liberty and property “loomed large in the minds and agendas of revolutionary-era constitutional framers, and it persisted to a large degree afterward.”

So what happened between then and now? As Rodriguez details it was the move from core harm prevention, “implemented principally through the common law,” to the more nebulous and expansive promotion of “the people’s welfare.” (For those who know a bit of Latin this was the move from sic utere tuo ut alienum non laedas to salus populi suprema lex esto.) This did not happen at any one moment but gradually through decades and, indeed, centuries. As Rodriguez also notes, this expansion was not the cause of a more activist government (as any historian of socialism, progressivism, or Bismarckian welfare statism will tell you) but also was not merely a result of those movements. The allowance in the courts of a more “plenary, minus rights” view allowed social reformers and legislators to then make their move. Thus, the expansion of the police power, in the American context, was symbiotic with more expansive, and less liberal, ideologies.

This is not to imply Rodriguez is critical of all these developments. If anything he is supportive of much of this story. With a moderate view of events he does not write in the tradition of someone like Robert Higgs in Crisis and Leviathan, lamenting the ratchet of power over freedom in a kind of reverse-Whig history that us classical liberals are familiar with. Instead, we receive more a “centrist-dad approach,” observing and not standing athwart the flow of history, pleased with much of its course, but offering advice about where things went off the rails.

Excesses and opportunities

Yet there are plenty of times where the police power has left the track of good governing. To give just one example Rodriguez highlights, the book provides plenty of side-eye to zoning.

The recent reversal in the conventional wisdom concerning the power of local governments to tell people where and how they can live and work has been quite astounding, with the Yes In My Backyard (YIMBY) movement standing as just one manifestation. Does that mean the police power itself should be seen differently now when it comes to zoning? While not fully joining forces with property rights theorists such as Richard Epstein, Rodriguez suggests the police power should adapt “as evidence reveals some of the deleterious effects of exclusionary zoning.” The same is true of other excesses of modern regulation where the upside to the public—the salus populi—is low. One of those being occupational licensing. Here he suggests the police power is tied to what is “reasonable” and that can change over time.

How to police these unreasonable excesses? Rodriguez could use some more answers. While judicial review certainly has its place—even a large place—in his view of American democracy, he has problems with much of it. This writer can agree with him that enforcing positive rights through judicial action is not a fruitful endeavor. But Rodriguez is also skeptical of other constitutional tools even those are embedded in our state constitutions. One is unenumerated rights, which he is mostly unsupportive of using the courts to enforce. Another is regulatory takings. While he voices enthusiasm for some other forms of judicial enforcement, such as equal protection for invidious discrimination, he has more hesitation than drive for most judicial pushback on the police power’s identified excesses. All that being said, it is hesitation, not dismissiveness. He seems open to some judicial review of some forms of regulatory overreach, including a wider understanding of what is “arbitrary.”

Of course, judges are not the only actors in this story. Rodriguez far prefers structural reforms, the checks and balances embedded in written and unwritten parts of our states’ constitutional systems. Some of this can be at the administrative level, such as additional layers of review of new policies, some through electoral reforms. And to some extent he suggests that the people—the ultimate source of the police power—are the ones who must do the work.

Curiously, Rodriguez does not address the idea we started with: that is, how courts could enforce limits on the police power without drawing upon rights. Is this just a historical anecdote or is it a plan for the future? Perhaps now that rights do all the work it’s what we’re left with. And maybe such a change would just be an exercise in nomenclature? After all, from our earliest days, drafters of our state constitutions inserted rights in them when they could have simply expected judges to rule that “bad” legislative actions were outside of the police power. How would this be different today? It may be that in the end rights are simply the language we use to describe the proper role of government, whether they be enumerated or, as I have argued elsewhere, unenumerated. If this is true, a renewed conversation on “the police power” may ultimately be a renewed conversation on the proper role of the state.

Which is a conversation we need to keep having. Whether the police power evolves back into a sic utere understanding or is at least cut down a bit to the satisfaction of centrist dads, Rodriguez’s analysis is a thoughtful way for us to get there.

Anthony Sanders is the Director of the Center for Judicial Engagement at the Institute for Justice.