A pending Supreme Court case that pits union rights against property rights began on a cold October morning in 2015 on a California strawberry plant farm near the Oregon border.

Mike Fahner, the third-generation owner of Cedar Point Nursery in Dorris, recalls a “frightening” scene: “We had strangers on bullhorns marching up and down through our buildings.” He cites a video of flag-waving union demonstrators he describes as an “invasion” and blames California’s law that gives organizers the right to access a grower’s property to make their case to farmworkers.

Union officials were blunt in response. “They’re absolutely lying about it being a trespass,” United Farm Workers of America (UFW) general counsel Mario Martínez said. “What they’re upset about is that their own workers went on strike. . . . The video they’ve circulated? Those are all Cedar Point workers. They’re not union organizers.”

The California Agricultural Labor Relations Board dismissed Cedar Point’s complaint, determining “the actions of the striking workers are not attributable to the UFW” organizers who were present, state officials told Cedar Point’s lawyer.

Fahner acknowledges he would be in the lawsuit no matter how polite or ill-mannered union organizers might be. “The right-to-access law, whether provided to unions or anybody to somebody’s personal private property, is wrong,” he said. “And it doesn’t exist anywhere else in the nation.”

But depending on how broadly the Supreme Court rules in the case it will consider Monday, it could have national implications for all sorts of instances in which the government authorizes entry onto a person’s property.

“It’s also about this larger issue of balancing government’s right to protect the public and individual property rights,” Victoria Hassid, chairwoman of the labor relations board, said. “The petitioners are really putting forward an incredibly extreme theory that would imperil a whole host of regulatory schemes at the local, state and federal level that go beyond labor: public health statutes, food and drug statutes, child welfare statutes, environmental statutes, tenants’ rights, consumer protection.”

Lawyers for the Pacific Legal Foundation, which is representing the growers, dispute that. But they acknowledge their goal is to limit government’s reach onto private property and to affirm the rights of property owners to exclude those they don’t want on their land.

The case requires the Supreme Court to consider what is called the “takings clause” of the Fifth Amendment to the Constitution: “Nor shall private property be taken for public use, without just compensation.”

That applies when government actually takes possession of private property, such as for eminent domain. But the Supreme Court has also said it applies when government regulates someone’s property to such a degree that it is practically the same thing: an easement for the public to cross someone’s land to get to the beach, for instance.

Cedar Point, as well as Fowler Packing in Fresno, disagrees with the state of California on whether the access granted to union organizers under the regulations can be considered a taking.

The law was passed in 1975 to “ensure peace in the agricultural fields” between workers and growers. It was the first to recognize farmworkers’ collective bargaining rights, an outgrowth of the movement led by César E. Chávez, Dolores Huerta and others.

It limits union access to no more than four 30-day periods in a calendar year and also restricts organizers to meeting with workers one hour before work, one hour during the lunch break and one hour after work. (The National Labor Relations Act also provides unions with access to workplaces but has no provision for farmworkers.)

The California Supreme Court upheld the rules on a 4-to-3 vote in 1976, and the provisions have gone unchallenged until now.

Hassid says the access is as necessary now as it was 45 years ago.

“Our job is not to necessarily say you should join a union,” Hassid said in an interview. “Our job is to ensure that if workers decide to do that, they have the tools available to them. And this case gets right to the heart of an incredibly critical tool for farmworkers when it comes to actually knowing those rights are available to them.”

Part of the workforce is undereducated, moves frequently, is hard to reach on social media and may face language barriers, Hassid said. She said they are often dependent on growers for transportation, making it difficult for organizers to reach them except when they are on the farms, sometimes in remote parts of the state.

Simply allowing organizers to come onto a grower’s land three times a day for a month is far from the “taking” of land the Constitution protects, California maintains.

“While the regulation may interfere with property owners’ right to exclude certain organizers for the brief periods of authorized access, it is not comparable to a permanent physical occupation,” the state said in its brief to the Supreme Court.

It notes that the justices have already ruled that way on the access to workplaces granted by the National Labor Relations Act, upon which the state law is modeled.

A panel of the U.S. Court of Appeals for the 9th Circuit agreed. But a move to reconsider the decision by the whole court sharply split the court’s liberal and conservative judges, with one predicting the Supreme Court would once again overturn the decision.

Pacific Legal Foundation lawyer Joshua P. Thompson told the Supreme Court in his brief that the 9th Circuit finding was “breathtaking in its scope: a government-authorized physical invasion of private property constitutes a per se [inherent] taking only where it permits access ‘24 hours a day, 365 days a year.’ ”

Even if California doesn’t claim that, Thompson wrote, it provides the court no test for deciding when restrictions would cross the line to become a taking.

As a policy matter, the growers say, the law is no longer needed, as fewer workers live on the property they work and can be reached for organizing purposes in many ways that didn’t exist in 1975.

Both sides in the dispute have gathered a large group of supporters for their position: local governments, unions and liberal constitutional advocates for California; the U.S. Chamber of Commerce, farm bureaus and conservative and libertarian legal groups for the growers.

And both sides can claim the Justice Department is on their side.

When President Donald Trump was in office, the department filed a 33-page brief supporting the growers, and agreeing the access was a taking.

“Providing indefinite authorization” for even periodic access “still deprives property owners of not only the right to exclude, but also the right to possess and use the portions of their property while invaded by those third parties,” the department’s brief stated.

But after President Biden was inaugurated, acting solicitor general Elizabeth Prelogar sent a four-paragraph letter to the Supreme Court saying the brief was no longer operative.

“It is therefore the position of the United States, in line with this court’s cases, that the California regulation — like the authorization of temporary entry by government officials for law enforcement, inspection, and similar purposes — does not constitute a per se taking,” Prelogar wrote.

Something else has changed since the 1970s: the court itself. The Supreme Court declined to review the California Supreme Court’s 1976 decision approving the regulations because it said there was no federal issues at stake.

But the court has grown more protective of property rights, and its conservative majority more skeptical of unions.

That was most evident in 2018. After a years-long campaign by conservative groups, the court ruled 5 to 4 that it was unconstitutional to allow public employee unions to require collective-bargaining fees from workers who choose not to join the union, a major blow for the U.S. labor movement.

To do so, the court had to overturn a 40-year-old precedent, prompting an angry dissent from the court’s liberals.

“There is no sugarcoating today’s opinion,” Justice Elena Kagan wrote. “The majority overthrows a decision entrenched in this Nation’s law — and in its economic life — for over 40 years.”

The California case is Cedar Point v. Hassid.