Under the Anti-Injunction Act, 26 U.S.C. §7421(a), taxpayers are barred from bringing suits “for the purpose of restraining the assessment or collection of any tax.” Accordingly, a taxpayer wishing to challenge a tax provision is generally required either to pay the tax and bring a suit seeking a refund in federal district court or dispute an assessment in Tax Court.

This past term, the U.S. Supreme Court addressed the scope of the Anti-Injunction Act in CIC Services v. Internal Revenue Service, 141 S. Ct. 1582 (2021). There, the court unanimously rejected the government’s argument that the Anti-Injunction Act barred a challenge to an IRS Notice requiring both taxpayers and their advisors to disclose information regarding transactions the government views as abusive on pain of both civil tax penalties and criminal prosecution. This column analyzes the court’s decision in CIC Services and considers its ramifications for future challenges to tax-related provisions.