OLYMPIA, Wash. — The state Supreme Court has tossed out a defamation lawsuit against two citizen groups who opposed a massive housing development on farmland in rural Pierce County, clarifying immunity from lawsuits designed to silence citizen complaints.

Yesterday's ruling, along with a new law passed by the Legislature this year, beefs up legal protections against so-called Strategic Lawsuits Against Public Participation — or SLAPPs.

The case stemmed from an 1,800-house development that Right-Price Recreation planned to build on farmland east of Tacoma. Two groups, the Connells Prairie Community Council and the Pierce County Rural Citizens Association, fought the development, testifying before the county council in 1998 that the plan violated the state's Growth Management Act.

Right-Price filed a lawsuit claiming slander, civil conspiracy and interference with the hearing process. Then it filed a motion seeking hundreds of documents from the groups, including financial statements, tax returns, membership lists, minutes of meetings and letters to public officials.

"They asked us for everything you've ever written," said Sharon Gain, a member of the Pierce County Rural Citizens Association. "Everything you've ever said to each other. It was horrible."

Shawn Newman, one of the groups' lawyers, said the lawsuit was typical of SLAPP suits.

"It was an intimidation lawsuit by a developer against a citizen group," Newman said. "The timing of these things [is] designed to scare the hell out of citizens. It morphs a political issue into a legal issue."

The groups fought the motion and asked for the case to be dismissed, arguing they were immune under both a 1989 state law and their constitutional right to petition the government. The Supreme Court's unanimous ruling yesterday agreed, saying the law protects such groups as long as they act in good faith.

"Right-Price totally failed to establish clear and convincing evidence that the groups' statements were made with actual malice," Justice Faith Ireland wrote.

The ruling sends the case back to Pierce County Superior Court for dismissal and an award of legal fees for the community groups.

Right-Price's attorney, Matthew Sweeney, refused to comment on the case. A telephone call to developer Tom Price was not immediately returned yesterday.

In the future, Newman said, citizens will enjoy stronger upfront protections against SLAPPs as they petition government agencies.

A law passed this year removes the good-faith requirement. The change is designed to make sure SLAPP lawsuits are dismissed quickly because the question of good faith won't need to be resolved. It also will allow citizens slapped with a SLAPP to seek as much as $10,000 in damages along with their legal costs. The law takes effect June 13.

Newman, who helped draft the law, calls it the toughest anti-SLAPP provision in the country.

"It's going to really give citizens a powerful hammer to beat back these intimidation ploys," Newman said.

The case is Right-Price Recreation v. Connells Prairie Community Council.