The Association of National Advertisers, which has been very keen on transparency in media deals, would like less of it when it comes to disclosure of donations to nonprofit organizations.

The group filed a “friend of the court” brief today asking the U.S. Supreme Court to reverse a California mandate requiring charities to reveal private donor information to the state government as a condition for fundraising.

The amicus brief was filed on behalf of the ANA and its ANA Nonprofit Federation, an organization the group acquired in 2018 that provides education, advocacy, sponsorship opportunities and ethical standards for nonprofits. The brief supports an appeal by nonprofits against a mandate by California Attorney General Xavier Becerra—who is also President Joe Biden’s nominee to be Health and Human Services secretary—requiring nonprofits to provide names and addresses of donors who give $5,000 or more in a year.

“ANA members work with and donate to numerous causes and missions that advance our society, and their ability to do so without state interference must be protected,” said ANA CEO Bob Liodice in a statement. “Our support of this appeal is of pivotal importance to ensure that our community’s generosity can continue without unreasonable donor disclosure mandates.”

The brief argues that disclosure laws create a “chilling effect on associational freedoms” and will adversely affect charitable giving.

Would-be donors have “many legitimate reasons to insist on anonymity,” according to the brief, and empirical data show many would be more reluctant to give if their confidentiality were at risk. That the California attorney general tries to keep the information confidential “is no consolation,” the brief says, because the information in the hands of state authorities “is vulnerable to disclosure through state right-to-know laws.”

The brief adds: “Donors are reluctant to put their private information in the hands of public prosecutors whose job descriptions extend well beyond enforcement of tax laws and who wield authority that can be subject to political motivations over which the donors have no control.”