Politico reports:

A nonprofit group founded by conservative political megadonors Charles and David Koch must disclose its largest givers to law enforcement authorities in California, a federal appeals court ruled Tuesday.

The Americans for Prosperity Foundation had argued that the state’s rules requiring filing of the donor list violate the First Amendment by discouraging individuals from giving and by exposing them to threats and harassment.

In 2016, the group persuaded a federal judge in Los Angeles to issue a permanent injunction against the requirement. U.S. District Court Judge Manuel Real said the state rarely used the information, but often disclosed it accidentally with charities’ public tax filings.

However, a three-judge panel of the 9th Circuit Court of Appeals unanimously reversed that ruling Tuesday, holding that the state had a legitimate need for the data and that the Koch-founded group had not shown a significant burden on donors. …

“To the extent the district court found actual chilling or a reasonable probability of harassment from confidential disclosure to the Attorney General, those findings are clearly erroneous,” Judge Raymond Fisher wrote In a 41-page opinion, joined by Judges Richard Paez and Jacqueline Nguyen.

“The mere possibility that some contributors may choose to withhold their support does not establish a substantial burden on First Amendment rights,” Fisher added. …

Fisher called it “undeniably” true that that some people connected to the Americans for Prosperity Foundation had been subjected to threats or harassment, but it was unclear whether that resulted from their ties to the foundation or from other activities. He also said that the court did not need to consider the dangers associated with public disclosure of the donor list, because the state has implemented a regulation that exempts the information from public release. …

The appeals court said it had “serious concern” about lapses that led to disclosure of the donor lists in the past, but said steps the state has taken to prevent those in the future were reasonable. Fisher also noted that the IRS already collects the same information and he described as “slight” the chances of the state accidentally releasing the group’s data in the future. …

Another conservative group, the Michigan-based Thomas More Law Center, pursued a parallel case against the California AG’s office over the donor filing requirement. That challenge was also rejected by the 9th Circuit Tuesday.

Americans for Prosperity Foundation spokesman Bill Riggs said the group plans to pursue the case further, but he did not indicate if that will involve a request for a larger, 11-judge 9th Circuit panel to rehear the case or for the Supreme Court to take it up.

“We are disappointed by the Ninth Circuit’s latest decision and believe it imperils people’s First Amendment right to freedom of speech and of association,” Riggs said in a statement. “Consistent with the protected, sensitive nature of our donors’ identities, the threat and chill they face from disclosure that was established during the trial of this case.”

For the record, let us not forget that the demand for donor lists that is being challenged in this case was made by former California Attorney General Kamala Harris. If you watched her performance during the Kavanaugh hearings, you’ll understand why conservative and libertarian donors might be disinclined to trust her and others like her with confidential information that could be used against them.