In a blow to the property-rights movement, the U.S. Supreme Court ruled yesterday against Lake Tahoe property owners who had argued that they were entitled to monetary compensation from the government for restrictions placed on use of their land. The origins of the legal battle stretch back two decades, to when the Tahoe Regional Planning Agency placed a three-year moratorium on development in the Lake Tahoe Basin to study possible environmental impacts. Property owners who bought land before the restrictions were enacted but were largely unable to develop it filed suit against the planning agency in 1984. The plaintiffs had been hoping for a blanket decision in favor of property owners, but the court ruled 6-3 that a temporary building moratorium is a necessary tool of government and does not automatically amount to a “takings” of private property. That’s good news for environmentalists and planners, who had been suffering from a string of unfavorable Supreme Court rulings.