What is the “police power”? Most often, the term is used as a synonym for the state’s (near unlimited) authority to regulate. But in a new book, Good Governing, Professor Daniel Rodriguez explores the power’s more limited historical roots in America. He explains that originally, the power was a tool for protecting private rights. It allowed the state to safeguard private property by preventing nuisances. Later, it evolved into a more active tool, allowing the state to promote economic development through public works. But even then, it remained anchored in public welfare: it allowed the state to act affirmatively only to advance the common good. It was only much later, after decades of litigation about public authority and private rights, that the power morphed into an essentially all-encompassing regulatory license. Yet now, that all-encompassing view has become the default one. It is so widely accepted that the police power’s original limits have been mostly forgotten.

This historical forgetfulness is more than an academic curiosity. Wielding their expanded authority, states have increasingly legislated in ways incompatible with the police power’s origins. Rather than simply promoting public welfare, they have intervened in markets, reallocated resources, and favored some private interests over others. That is, they have used the police power to pick winners and losers.

Maybe the starkest example comes from how states and cities are regulating tech companies. Increasingly, state and local officials target tech companies for exceptional burdens. They load the companies down with requirements ranging from policy mandates to targeted taxes. And while they adopt these requirements under the guise of the police power, they rarely connect them to any public interest in safety or health. Instead, they tacitly—and sometimes explicitly—target the companies out of pure dislike.

While few will shed tears for “big tech,” the tech companies’ predicament highlights a broader problem. If states and cities can regulate private firms for no better reason than naked spite, then the police power has truly broken free of its historical moorings. It has mutated from a public-welfare tool into an infinite regulatory power. Its traditional limits have been lost. It has made the law a matter of legislative will, and it has made private rights a matter of state indulgence.

Maybe, then, it is time to start remembering. Maybe Good Governing can help.

From Sic Utere to Salus Populus

At bottom, Good Governing is an exercise in historical exhumation. Professor Rodriguez sweeps away the sediment of time and traces the police power back to its roots. He writes that the power originated in the Founding era, drawn from contemporary ideas about the nature of government and “social contract.” Influential thinkers like John Locke and Jean-Jacques Rousseau argued that civil government was the product of consent: people agreed to join civil society because it allowed them to safeguard their preexisting rights. Yes, by submitting to state authority, they surrendered some liberty; they agreed to abide by the community’s rules. But that surrender was conditional. People consented to state regulation only when the regulation would promote the common good. In other words, they gave away some of their rights to better protect their reserved ones.

That idea gave birth to the “sic utere” theory of government. Roughly speaking, that theory saw civil government as a way to control negative externalities. Government could limit a person’s rights, but only to prevent harm to others. For example, a person might have a general right to use her property as she saw fit, such as using it to build a factory. But if her factory blew smoke onto her neighbor’s property, she would injure her neighbor’s rights. And that’s where the police power came in. The police power allowed the state to limit one person’s rights to stop her from injuring others. It was essentially an anti-nuisance tool—one designed to leave everyone safer and better off.   

But that view of the police power didn’t last forever. As the 19th century marched on, people started to see the state as more than just an anti-nuisance watchdog. Instead, they increasingly saw it as an engine for promoting wealth. New technologies like steam power and the railroad promised new levels of economic growth. But that growth could be achieved only by assembling vast resources. Someone had to build the harbors; someone had to dig the canals. And increasingly, that someone was (at least in part) the state.    

Thus was born the “salus populi” theory. Salus populi is Latin for (roughly speaking) the public good. It means that the state can not only prevent harm, but also promote welfare. It can do things like buy up land, construct roads, and erect dams. It is not only a fence tender, but a bridge builder; it not only protects private wealth, but creates it. Or at least, it creates the conditions necessary for private wealth. By acting affirmatively, it can promote private flourishing and a greater common good.

Reaction and Erasure

This expanded vision of the police power didn’t stop with public works. It was only a short step from dams and bridges to intervention in the market. In the late 19th century, regulators increasingly experimented with wage-and-hour laws, antitrust laws, licensing schemes, and even price controls. They injected the state into areas once left to private law, including commerce, competition, and employment. These areas all became the subjects of pervasive public regulation.

Those regulations ultimately sparked a constitutional conflict. In the years immediately after Reconstruction, courts had read the Fourteenth Amendment narrowly. The U.S. Supreme Court itself initially rejected the Fourteenth Amendment as a possible limit on the police power. But as the regulatory wave swelled, the Court increasingly looked for ways to stem the tide. Wielding the Due Process Clause, it struck down a swath of novel social and economic regulation. It especially disfavored “class legislation”—i.e., laws designed to favor one group over another. That kind of law, it said, aimed not to protect private rights, or even to promote the general welfare; it aimed simply to take from A and give to B. It was therefore an improper exercise of the state’s police power.

The judicial reaction, of course, produced a counter-reaction. The Court was excoriated for second-guessing the judgment of elected officials. And under pressure, it retreated. In cases like Williamson v. Lee Optical, it effectively abandoned the project of supervising economic regulation through due process. No longer would the Court second-guess social or economic laws. Those laws would instead be a matter of legislative judgment—a judgment about which the Constitution had little to say.

In theory, the judicial retreat shouldn’t have changed the police power itself. The power should still have been limited by its original scope. But in practice, the power emerged stronger than ever. As the Supreme Court abandoned the field, legislators and agency administrators charged in. These officials wielded a supercharged form of regulatory power—one freed from its historical foundations. The power was no longer a tool for preventing harm, or even for promoting common interests. It was instead a power to do whatever the state wanted to do.

A Power to Punish

The fruits of that shift are being reaped today. Now, public officials face few limits on their policy prerogatives. As long as they can articulate some non-risible government purpose, they can regulate any way they want. And increasingly, they want to target specific companies—especially tech companies.

The examples could fill volumes. To take a few recent ones, in 2020, California passed a restrictive worker-classification law, AB 5. Though AB 5 affected many industries, its author, Assemblymember Lorena Gonzalez, effectively admitted that she was targeting a handful of app-based platforms. The platforms ultimately avoided the fallout by sponsoring and passing their own statewide voter initiative. But Gonzalez wasn’t deterred. Only a few years later, she pushed through another targeted law, this one regulating work quotas in warehouses. During the drafting process, she again admitted that she was targeting a single tech company. Evidently, using the police power to punish specific companies was nothing to be embarrassed about.

While Gonzalez may have been uniquely vocal, she was hardly alone. Also in 2020, San Francisco’s board of supervisors passed a commission-cap law also aimed at app-based delivery platforms. The board effectively wrote the law to shift revenue from the platforms to local restaurants. The next year, New York City councilmembers followed up with a similar commission-cap law, this one also calibrated to shift wealth from the companies to local interests. The council made little effort to justify the law as necessary for public health or safety. Instead, it presented the law for what it was: a naked transfer from one set of private parties to another.   

Brazen as these laws were, they paled in comparison to the regulatory wave in Seattle. Starting in 2022, Seattle practically drowned app-based platforms in new requirements. These requirements ranged from detailed reporting to complex pay requirements to targeted taxes. The requirements proved so burdensome that they drove one major company to abandon the city. And given the rhetoric of some city councilors, one suspects that was the goal all along.

To be sure, few people will shed tears for tech companies. These companies are among the most dynamic and successful in world history. But even so, their predicament shows how far the police power has been stretched. The power is no longer simply a tool to protect people from private harm. Nor is it merely a lever for promoting public welfare. It is now a weapon—one states and cities can wield to punish disfavored citizens. It has broken free of its historical moorings; sic utere has become potestas puniendi.

Professor Rodriguez didn’t set out to write a book about tech companies. He was instead writing about the police power’s historical evolution. But tech companies nevertheless underline his point. We have forgotten where the police power came from; and by forgetting, we have lost any real limits on the power’s use. Maybe, then, Good Governing can help us remember.

Note from the Editor: The Federalist Society takes no positions on particular legal and public policy matters. Any expressions of opinion are those of the author. We welcome responses to the views presented here. To join the debate, please email us at [email protected].