WASHINGTON (AP) — The Supreme Court has turned away an appeal from same-sex marriage opponents in California who want to keep the identities of their campaign donors secret.

The justices on Monday let stand a lower court ruling against ProtectMarriage.com, the National Organization for Marriage and other supporters of a 2008 ballot initiative that outlawed same-sex marriages in California until the ban was overturned five years later.

The groups sought to conceal their past and future campaign finance records because they feared harassment of donors. The 9th U.S. Circuit Court of Appeals ruled against them in part because the names have been publicly available for five years.

State law requires political committees to identify those who contribute more than $100 during or after a campaign, along with the donor’s address, occupation and employer.

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