Goldstein and others (defendants) operated a plant in which musical recordings on tape or phonograph could be duplicated, labeled, packaged, and sold at retail to the public. The duplication was unauthorized and amounted to piracy of the copied recordings. The State of California (plaintiff) had a state statute, § 635h of the California Penal Code, that prohibited making any unauthorized copy of a musical performance from a tape or record with the intention of selling the copy. Section 635h granted a copyright in those recordings for an indefinite period. Federal law under the Copyright Act of 1909 did not address the copyright status of recordings of musical performances. California brought charges against the defendants for violation of § 635h. The defendants moved to dismiss the claim, alleging that § 635h was prohibited under the Copyright Clause and the Supremacy Clause of the United States Constitution. The district court denied the motion. The defendants appealed, and the court of appeals affirmed the decision. The defendants then petitioned for a writ of certiorari.