In the United States v. Kapp et al., 1937, the Supreme Court ruled on a case involving an alleged violation of the Sherman Anti-Trust Act by several meatpacking companies and their executives. The defendants were accused of conspiring to fix prices and control sales in Chicago's wholesale fresh meat market, which was deemed as monopolistic behavior that violated federal law. However, they argued that their actions were justified under Section 6 of the Clayton Act because they constituted cooperative marketing efforts among agricultural producers. The lower court had dismissed this argument and convicted them for violating antitrust laws. The Supreme Court reversed these convictions upon appeal, ruling that Congress intended to exempt such cooperative marketing arrangements from anti-trust prosecution under Section 6 of the Clayton Act when it passed legislation like Capper-Volstead Act protecting farmers' cooperatives from antitrust action. Therefore, even though these activities might otherwise be considered illegal restraints on trade or attempts to monopolize markets under Sherman Antitrust Law, they are permissible if done by agricultural organizations or associations acting in good faith for mutual help without any profit motive.

In the dissenting opinion for United States v. Kapp et al., Justice McReynolds disagreed with the majority's decision to uphold a conviction under the Sherman Anti-Trust Act. He argued that there was no evidence of an intent to monopolize or restrain trade, which is necessary for a violation of this act. Instead, he believed that the defendants were simply trying to protect their business interests in response to market conditions and government regulations. Furthermore, he contended that it was unfair and unreasonable to apply anti-trust laws in such circumstances where businesses are forced by external factors into cooperative arrangements just for survival purposes rather than any malicious intent towards competition or monopoly creation.