The Denver Post: Two conservative taxpayer advocacy groups filed suit Wednesday against Denver over campaign finance disclosure rules that they say will violate the privacy rights of their donors when the groups get involved in city elections.

The lawsuit, filed by the Phoenix-based Goldwater Institute on behalf of the two groups, says changes approved by the City Council in September violate the free speech provision of the First Amendment. The city ordinance requires clubs, associations, corporations and groups that advocate for or against local ballot measures to meet the disclosure requirements of issue committees once they raise and spend at least $500.

Once it passes that threshold, an issue committee must identify by name and address each donor who gave $50 or more within that calendar year.

“We have donors who like to remain anonymous, and we’d like to honor their requests,” said Marty Neilson of the Colorado Union of Taxpayers. “We think this is an unconstitutional ordinance.”

The lawsuit was filed in Denver District Court. Also joining as a plaintiff is the TABOR Committee, which advocates for protecting the state’s voter-passed Taxpayer’s Bill of Rights.

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