The U.S. Supreme Court case Jacob Ruppert, a Corporation v. Caffey (1919) centered on the constitutionality of the War Prohibition Act of 1918, which banned the sale and manufacture of alcoholic beverages with more than 2.75% alcohol content during World War I to conserve resources for war efforts. The plaintiff, Jacob Ruppert Inc., was a brewery that challenged this act as unconstitutional because it exceeded Congress's wartime powers and violated their Fifth Amendment rights by depriving them of property without due process or just compensation. However, in its ruling, the Supreme Court upheld the validity of this legislation under Congress's broad power to regulate commerce during times of war and found no violation against constitutional rights since brewing beer is not an inherent right but subject to regulation by law.

In the dissenting opinion for Jacob Ruppert v. Caffey, Justice McReynolds disagreed with the majority's interpretation of the 18th Amendment and Volstead Act. He argued that these laws were not intended to prohibit all beverages containing alcohol, but only those which could be considered intoxicating in ordinary use. According to him, this would exclude beer from prohibition as it was generally consumed without causing drunkenness. Furthermore, he contended that if Congress had intended such a broad ban on alcoholic substances they would have clearly stated so in their legislation rather than leaving it open to judicial interpretation. Therefore, he believed that by upholding the Prohibition Commissioner’s decision to include beer under prohibited items despite its low alcohol content was an overreach of power and against legislative intent.