From a legal or regulatory standpoint, the beer industry, like many things, can be divided into three periods: there is the period after Repeal that the three-tier system reigned without challenge until 2005. Then there was the Granholm Supreme Court decision which checked the power of the 21st Amendment by stating that states couldn't use the Amendment to defy the Commerce Clause, which mandates that in-state wineries should be treated the same as out-of-state wineries.