WASHINGTON — Despite a near unanimous Supreme Court decision Thursday that Washington state can release the names of the roughly 138,000 people who signed ballot petitions to overturn a same-sex domestic partnership law, the case is far from over.

Religious conservatives who sought to block release of the signatures, and who fear harassment and retaliation if the names are made public, will return to federal court in Tacoma, Wash., to ask for a specific exemption to the state's Public Records Act.

Courts have allowed such exemptions on a case-by-case basis, and the high court said its ruling doesn't "foreclose success" in a narrower challenge.

In a 13-page page decision by Chief Justice John Roberts Jr., the court found that the Public Records Act covered the names of those who sign initiative and referendum petitions. Roberts said the disclosure of the names wouldn't as a "general matter" violate the First Amendment.

However, the court held open the possibility that the names could be withheld under certain circumstances.

Roberts wrote that the state has a responsibility to promote "transparency and accountability" in the electoral process, adding that the release of the names of petition signers would help "root out fraud" and "ferret out" invalid signatures that could result from simple mistakes.

The ruling noted that just because the court rejected a broad challenge to the disclosure law, it didn't block a narrower challenge that could be successful if it shows a "reasonable probability" that people will be subject to "threats, harassment, or reprisals from either government officials or private parties" if their names are released.

The 8-1 decision wasn't unexpected, as justices from the right and the left seemed skeptical during oral arguments in late April about the broad effort to exempt petition signers from the state disclosure act. The lone dissenting justice was Clarence Thomas, though others who agreed with Roberts wrote their own concurring opinions.

Protect Marriage Washington, a group opposed to the law, which voters narrowly upheld, had sought to keep the signatures secret because it feared retaliation from gay rights supporters. The state argued that the Public Records Act required the release of those signing initiative and referenda petitions.

The case had attracted national attention not only because it involved gay rights, but also because it could serve as a precedent for other states that have tough public disclosure laws.

The names still haven't been released.

Though disappointed with the ruling, James Bopp Jr., an Indiana attorney who argued the case before the Supreme Court for Protect Marriage Washington, said he's convinced his clients will prevail when the case returns to the lower court.

"They certainly reaffirmed we can seek our exemption," Bopp said. "They laid the groundwork for us to be successful. There is ample evidence that supporters of traditional marriage are being harassed because of their political views."

Bopp said his group would have preferred a broader ruling on whether the disclosure law covered the names of petition signers.

"But they decided everyone is on their own," he said. "If that's what they insist on, then we will go do it."

Washington Attorney General Rob McKenna said he was pleased by the Supreme Court ruling and was convinced the state would prevail when the case returns to the lower court.

McKenna said there was little evidence that signers of the petition faced harassment or intimidation. He said the names of people who contributed to the R71 campaign were previously disclosed and there was no evidence they were being harassed.

"We will argue the petitioners have not brought forward enough evidence," McKenna said.

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