In the 1950 case of Libby, McNeill & Libby v. United States, the U.S Supreme Court ruled in favor of the government and upheld a conviction against a food processing company for violating wartime price controls. The company was accused of selling canned foods at prices above those set by the Emergency Price Control Act during World War II. The defense argued that they were not aware that their actions violated any laws as they believed their contracts predated these regulations and thus should be exempted from them. However, this argument was rejected by Justice Felix Frankfurter who stated ignorance or misunderstanding about new laws does not excuse noncompliance with them especially when it comes to public interest matters such as inflation control during war times.

In the dissenting opinion for Libby, McNeill & Libby v. United States, Justice Douglas argued that the majority's decision to uphold a conviction based on an indictment that did not specify which acts were illegal was fundamentally flawed. He contended that this lack of specificity violated the defendants' constitutional rights by denying them fair notice of what they had allegedly done wrong and preventing them from preparing an adequate defense. Furthermore, he criticized the majority for allowing a jury to convict without having to agree on which specific actions constituted criminal behavior. In his view, this approach undermined essential principles of justice and due process by permitting convictions based on vague or ambiguous charges.