The Supreme Court, in a second major legal victory for developers and landowners in three weeks, yesterday limited the power of local governments to extract concessions from property owners in exchange for building permits.

The court, ruling in a California case, held that governments may not place conditions on development that are not directly related to the development itself. The decision "raises questions" about zoning regulations that call for developers to provide amenities that are not an integral part of their project, such as requiring a developer to build low-income housing on one site in exchange for permission to build an office building on another, real estate experts said yesterday.

By a 5 to 4 vote, the court overturned a decision by California officials that compelled a couple to grant the public access to the beach front between the ocean and their home in exchange for permission to tear down and rebuild the house.

The court ruled that the California Coastal Commission's condition that the owners offer a permanent public easement to their ocean front in exchange for permission to build constituted a "taking" under the Fifth and Fourteenth Amendments, for which the state must compensate the landowners.

Writing for the majority, Justice Antonin Scalia said when a governmental agency imposes a restriction on owners' use of their property, that restriction must be directly related to a specific public purpose that is part of the agency's mandate.

"In short, unless the permit condition serves the same governmental purpose . . . the building restriction is not a valid regulation of land use but 'an out-and-out plan of extortion,' " Scalia wrote.

Scalia was joined by Chief Justice William A. Rehnquist and Justices Byron R. White, Lewis F. Powell and Sandra Day O'Connor.

In another major land use decision, handed down three weeks ago, the court ruled for the first time that property owners must be compensated when they are deprived of the use of their land, even temporarily, by zoning or other regulations. That case was First English Evangelical Lutheran Church of Glendale v. County of Los Angeles, Calif.

While the First English case did not make it any easier for a landowner to prove that a regulation amounted to a taking, state and local government organizations said at the time that the decision would have a serious "chilling" effect on the freedom of local governments to regulate because they would be liable for damages if a regulation was later found to constitute a taking.

"The psychological impact of the two decisions is considerable," said Gus Bauman, general counsel for the National Association of Home Builders. "The court is saying to localities that you've got to regulate fairly. If you are going to be harsh, you risk running afoul of the takings clause. And if you run afoul of that, you will pay for it."

In a third land use decision, handed down by the court earlier this year, however, the court upheld the constitutionality of a state regulation that limited the amount of coal that may be taken from underground mines. The court said the regulation was valid because it protected public health and safety and did not deprive the property owner of all economic use of the land.

Developers and conservative public-interest groups praised the court for yesterday's decision in the Nollan case, saying that the decision could lead to a reassessment of the constitutionality of zoning regulations that "overreach."

"This decision establishes reasonable limits on government power in the land-use planning process," said Ronald A. Zumbrun, president of the Pacific Legal Foundation, a California group that promotes private property rights and that represented the plaintiffs in the case. "The court has outlawed the exaction game, where government uses legal extortion in the permit and licensing process to accommodate the same end."

Groups representing state and local governments, however, said they do not consider the Nollan case as far-reaching as developers claim.

"The court clearly said that if a {jurisdiction} has the power to prohibit development, they have the power to regulate it," said Benna Ruth Solomon, chief counsel for the State and Local Legal Center, a group that represents seven national organizations of state and local government officials.

Lee Ruck, general council for the National Association of Counties, said that the court took the first step in answering the question of what kind of regulation constitutes a taking, but that the court at the same time "raised as many quesions as it answered."

Ruck said that conditions tied to zoning approvals, such as impact fees for roads and low-income housing or land donations for schools, would have to be assessed individually to say whether they amounted to illegal takings.

In the Nollan case, Scalia said that the California Coastal Commission's belief that "the public interest will be served by a continuous strip of publicly accessible beach along the coast . . . is a good idea, but that does not establish that the Nollans {and other coastal residents} alone can be compelled to contribute to its realization."

He said that the commission's public purpose in requiring the easement -- that is was necessary to assist the public in overcoming the "psychological barrier" imposed by construction along the waterfront -- was not directly related to the easement. Requiring the Nollans to provide public access to the beach did not address the problem of the construction obscuring the waterfront, Scalia said, and therefore was a taking rather than an appropriate zoning regulation.

In a dissenting opinion, Justice William J. Brennan, joined by Justice Thurgood Marshall, said that the "court's insistence on a precise fit between the forms of burden and condition . . . would penalize the commission for its flexibility, hampering the ability to fulfill its public trust mandate."

Justice John Paul Stevens, joined by Justice Harry A. Blackmun in a second dissent, criticized the court for its decision, saying that "even the wisest lawyers would have to acknowledge great uncertainty about the scope of this court's takings jurisprudence." Because of the First English case, however, he said, "local governments and officials must pay the price for the necessarily vague standards in this area of the law."