Article XXVIII of the Colorado Constitution requires any group supporting or opposing a ballot initiative to register as an “issue committee” and comply with many regulations, such as disclosing the identity of anyone who has donated more than $20. Or, should the state find that a group of citizens has as its major purpose supporting or opposing such a ballot issue, state law imposes registration and compliance requirements, including contribution limits. In 2005, political opponents filed a complaint against the Independence Institute for not complying with such regulations when it spoke against a ballot initiative. Although the think tank eventually beat back this challenge, the litigation proved expensive and time-consuming—so the Institute decided to challenge the law as an unconstitutional abridgement of its free speech rights. The Colorado courts rejected those claims, and the Independence Institute, represented by the Institute for Justice, now wants the U.S. Supreme Court to review those decisions. Cato has joined the Wyoming Liberty Group, the Center for Competitive Politics, the Sam Adams Alliance, the Montana Policy Institute, and the Goldwater Institute on a brief supporting the Independence Institute. We argue that Colorado’s ballot campaign regulations run roughshod over constitutional protections for political speech and association, which lie at the very heart of the First Amendment—particularly for think tanks and other organizations that regularly comment on public policy matters. Loss of these First Amendment protections will chill think tanks’ future attempts to educate the public about issues that are the subject of ballot campaigns. The Court should thus review this case and ensure that citizens maintain their associational rights—including the right to remain anonymous when donating to non-profits—and associations their freedom of expression.