Justice Anthony Kennedy begins his opinion for the Court by extolling the Sherman Antitrust Act as "a central safeguard for the Nation's free market structures.

[5] To address this, the Court in Parker v. Brown (1943) granted California immunity from federal antitrust laws after the state created a New Deal raisin cartel.

Statehouses happily delegated Parker immunity to trade associations and when attorneys began using this delegation to set a price floor the Court in Goldfarb v. Virginia State Bar (1975) found Parker immunity required what Justice Kennedy calls “more than a mere facade of state involvement”.

[7] After California delegated price fixing authority directly to wine merchants, the Court in California Retail Liquor Dealers Ass'n v. Midcal Aluminum, Inc. (1980) began limiting immunity to where the State has articulated a clear anticompetitive policy and the State provides active supervision of the anticompetitive conduct.

[12] Justice Alito then recalls that when the Sherman Act was enacted, Congress's Commerce Clause power was much smaller and that at the time the States frequently set price controls.

[13] As such, Justice Alito believes denying the Dentists Board antitrust immunity “diminishes our traditional respect for federalism and state sovereignty”.