On Friday morning, the U.S. Supreme Court, in a landmark decision, struck down California’s demand that nonprofit advocacy groups turn over confidential information about their donors. The 6-3 ruling in Americans for Prosperity Foundation v. Bonta is considered a major victory for First Amendment advocates.

At issue was a dispute that began in 2014, when the Thomas More Law Center and the Americans for Prosperity Foundation went to federal court to challenge California’s rule.

“The case ends more than a decade of litigation that began when then-Attorney General Kamala Harris abruptly ended the practice that allowed nonprofits to turn in their annual reports with private information redacted, as a security measure. That had been allowed for many years, since if the Attorney General’s office ever actually needed such information, it could easily get it in many other ways—such as a subpoena or audit,” explains Timothy Sandefur of the Goldwater Institute in a blog post. “But in 2010, Harris ordered any nonprofit that collected money in California to hand over copies of their unredacted IRS paperwork. That information would be placed into a government database that Harris promised would be kept confidential. Of course, it wasn’t—a trial judge later found almost 2,000 instances in which Harris’s office allowed this information to be publicly circulated. (The Goldwater Institute received such a demand, but refused to disclose this information.)”

Chief Justice John Roberts wrote the majority opinion which reverses the 9th Circuit Court opinion.

In his blog post, Sandefur says the Court’s ruling “vindicates the privacy rights of millions of Americans who choose to contribute to nonprofit organizations that articulate the political, cultural, or religious values they hold dear. That choice is guaranteed by the First Amendment—yet many federal, state, and local officials continue to devote their powers to stripping donors of their privacy rights whenever they exercise that constitutional freedom. This is often done under the guise of “transparency,” but transparency is for government—privacy is for people. Today’s decision is a victory for the free speech rights of all Americans, whatever their ideological background—and we look forward to continuing the fight for freedom of speech and privacy at the federal, state, and local levels.”