In Granholm v Heald, 544 U.S. 460 (2005), the U.S. Supreme Court held that state laws that allow in-state wineries to directly ship alcohol to consumers, but prohibit out-of-state wineries to do the same, run afoul of the Dormant Commerce Clause in light of the 21st Amendment. By a vote of 5-4, the majority held that discriminating against the out-of-state wineries was unconstitutional, despite the authority granted to states under the 21st Amendment to regulate the sale of alcohol.
