In the 1944 case United States v. Johnson et al., the Supreme Court ruled on a matter involving false advertising claims made by a dental company. The defendants, operating as United States Dental Co., were charged with using mails to defraud through misrepresentation of their product's capabilities and endorsements in violation of federal law. They argued that they had not committed fraud because their customers received some value from their products, even if it was less than promised. However, the court rejected this argument stating that fraudulent intent can exist even when there is partial performance or some benefit conferred upon another party involved in an exchange transaction. Therefore, despite delivering a product which provided some level of service to its users, U.S Dental Co.'s misleading advertisements constituted mail fraud under federal law.

The dissenting opinion in the United States v. Johnson et al., 1944 case, was delivered by Justice Robert H. Jackson and joined by Justices Frank Murphy and Wiley Rutledge. They disagreed with the majority's decision to uphold a conviction for mail fraud based on false statements made about dental products sold through interstate commerce. The dissent argued that this interpretation of the federal mail fraud statute was overly broad, potentially criminalizing any misrepresentation in business dealings regardless of intent or harm caused. They contended that such an expansive reading could lead to arbitrary enforcement and infringe upon states' rights to regulate their own commercial practices, thus undermining federalism principles inherent in U.S law system.