The California Coastal Act for decades has scaled back mega-hotels, protected wetlands and, above all, declared that access to the beach was a fundamental right guaranteed to everyone.

But that very principle could be dismantled in the latest chapter of an all-out legal battle that began as a local dispute over a locked gate in San Mateo County.

On one side, property owner and Silicon Valley billionaire Vinod Khosla wants Martins Beach, a secluded crescent-shaped stretch of sand and bluffs, to himself. On the other, generations of beachgoers demand continued access to a path long used by the public. The squabble has spurred a spate of lawsuits that now focus on whether Khosla needs state permission to gate off the road — and a string of California courts has said he does.

Unwilling to back down, Khosla is now appealing to the U.S. Supreme Court over his right to shut out the public. His latest argument not only challenges the constitutionality of the Coastal Act — if taken up by the nation's highest court, it would put into question long-established land use procedures and any state's power to regulate development anywhere.

Ralph Faust, who was the commission's general counsel from 1986 to 2006, said said a striking difference between the Nollan case and Martins Beach is that Khosla is challenging the Coastal Act "as written, not as it's applied."

Nollan applied for a permit but didn't like the stipulations the commission required, so he challenged them, Faust said. Khosla is skipping that step altogether and arguing that the requirement to seek a permit — as well as the state court injunction to maintain the status quo of keeping the gate open while the matter is being decided — violates his rights as a property owner.

"That's a pretty stunningly broad attack on state government," Faust said. "If he were to win on that and just get a declaration that the Coastal Act could not possibly be constitutionally interpreted to require a permit for that kind of development — that would be just huge."

The Nollan case unfolded in unexpected ways and to this day affects the way access rights are argued and how land should be set aside for the public, Faust said. Should the Supreme Court take up Khosla's appeal, the implications are beyond imaginable.

"Just because you think you know what the situation is when you're talking about a case, doesn't mean that's how it's going to look if the Supreme Court actually decides something," he said.

"These things take on a life of their own."

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