Sales tax harmonization is a term often associated with European countries adopting tax policies that match their neighbors in close proximity. In the state tax world, the same is true, and Tax Analysts covers the Multistate Tax Commission's model statutes that encourage uniform state tax policy, state legislation, and court decisions that attempt to harmonize tax policy across the states.

Litigation in state courts across the country has recently skyrocketed as states that adopted the Multistate Compact's corporate income apportionment formula have retroactively repealed those laws in place of revenue-favorable apportionment formulas. Litigation is ongoing in states like Michigan, Minnesota, California, Texas, and Oregon.

Tax Analysts covers Congress's legislative proposals to harmonize state sales tax policy, tracking bills like the Marketplace Fairness Act and other legislation that would mandate some aspects of state tax policy. Reporters also cover state and federal court litigation on tax harmonization, like U.S. Supreme Court Justice Kennedy's concurring opinion in Direct Marketing Association v. Brohl, calling for a challenge to a 1992 Supreme Court case only allowing sales tax collection when there is a physical presence in the state, Quill Corp. v North Dakota. Kennedy's call for a challenge to one of the Court's own decisions sent shockwaves throughout the state tax world, and Tax Analysts spoke with practitioners and government tax officials, and it also covered a speech by a federal appellate judge on the implications not only in the state tax world, but how the majority opinion's decision affects federal tax administration as well.

Tax Analysts consistently and promptly publishes all relevant developments regarding sales tax harmonization, including proposals and litigation. To stay up to date on all tax-related topics, subscribe to Tax Notes Today Federal.