California labor law forces agricultural businesses to allow union organizers onto their property three times a day for 120 days of the year. Cedar Point Nursery has a strawberry farm in northern California. At 5:00 am one day during the heart of harvest season, union organizers entered Cedar Point’s property with bullhorns in hand. As the workers were preparing strawberry plants for shipment, the organizers enjoined the workers to unionize.

Cedar Point filed suit in federal court, arguing that the California law allows for the uncompensated taking of their property in violation of the Fifth Amendment’s Takings Clause. While that might seem like a strange argument because state did not physically commandeer Cedar Point’s property, imagine if your state passed a law allowing people to enter your home on 120 days of the year. A taking can arise from regulations that seriously interfere with ownership, not just the physical occupation or commandeering of property.

The Takings Clause is clear: “nor shall private property be taken for public use, without just compensation.” In 1922, in Pennsylvania Coal v. Mahon, Justice Oliver Wendell Holmes wrote that if a regulation “goes too far,” it is akin to a “classic” confiscation. In the 70s, in Penn Central v. New York City, the Supreme Court ruled that measuring whether a regulation “goes too far” means engaging in “essentially ad hoc, factual inquiries” that differ in each case. But in Loretto and Lucas, the Court clarified that physical invasions, however minor, are “per se takings” not subject to Penn Central’s balancing test.

California argues that its law is not a per se taking because it is not “permanent and continuous.” Using Penn Central’s highly deferential test, the Ninth Circuit was more than happy to oblige the Golden State. But the Ninth Circuit missed an opportunity to follow what the longstanding Anglo-American common law makes clear: That the “right to exclude” and other fundamental attributes of ownership—the sticks in the bundle of property rights—deserve Loretto’s categorical protection.

Cato, joined by the National Federation of Independent Business Legal Center, has filed an amicus brief to urge the Supreme Court to review Cedar Point’s case. We ask the Court to accord the right to exclude the same constitutional defense as in Loretto and Lucas. The only difference between this case and Loretto is the duration of the taking. But the right to exclude is all or nothing. Occasionally the right to exclude can be overridden to accommodate serious public needs, but those are rare occasions. Even if unionizing workers is a serious public need, unions have myriad ways to try to organize workers other than invading private property. From William Blackstone to Richard Epstein, legal scholars have recognized that the right to exclude is essential to private ownership—without it, property (and liberty) cannot be used to its fullest.

A regulation that disrupts an owner’s right to exclude others from their property, however slight, effects a total interference with that right. When it comes to the right to exclude, there is no practical difference between classic and regulatory takings. Whatever label a court applies, the result is the same: The owner cannot at all times choose who enters their property. The Court should take the case and clarify that the Takings Clause protects private property by protecting the fundamental elements of ownership.