"A state cannot simply ban all private contributions to candidates or causes. Such a law would certainly violate the associational and speech rights recognized in the First Amendment. Isenhart, no doubt mindful of how private donors supposedly undermine his goal of requiring the government to subsidize political campaigns, has suggested a novel idea.
He's simply proposing to tax every contribution over $250 to any campaign or political action committee at a rate of five percent. His bill, House File 140, would also tax independent ads by political groups at five percent."
Iowa tax on political speech proposed
Center for Competitive Politics:
