Granholm, et al. v. Heald, et al., Supreme Court of the United States, May 16, 2005 [ruling that states may not pass laws banning out-of-state wineries from shipping wine directly to customers in-state]. Excerpt from the majority opinion by Justice Kennedy:
We hold that the laws in both States discriminate against interstate commerce in violation of the Commerce Clause, Art. I, §8, cl. 3, and that the discrimination is neither authorized nor permitted by the Twenty-first Amendment. Accordingly, we affirm the judgment of the Court of Appeals for the Sixth Circuit, which invalidated the Michigan laws; and we reverse the judgment of the Court of Appeals for the Second Circuit, which upheld the New York laws.
Read the full text of the opinion here [PDF]. Reported in JURIST's Paper Chase here.