In the case of Rosenberg et al. v. United States in 1952, Julius and Ethel Rosenberg were convicted for conspiring to commit espionage by passing atomic bomb secrets to the Soviet Union during World War II. The Rosenbergs appealed their conviction on several grounds including that they had been tried under the wrong law, that there was insufficient evidence against them, and that their death sentences were cruel and unusual punishment. They also claimed a violation of due process because they weren't allowed to see certain classified documents used as evidence against them at trial. The Supreme Court upheld both their convictions and sentences with Justice William O. Douglas dissenting on procedural grounds related to timing issues surrounding when the court agreed to hear arguments in this case; he did not express an opinion regarding guilt or innocence or appropriateness of sentence. This decision marked a significant moment in Cold War history as it led directly to execution of Julius and Ethel Rosenberg - making them first U.S citizens executed for espionage-related crimes during peacetime.

In the dissenting opinion for Rosenberg et al. v. United States, Justice William O. Douglas argued that the death penalty was too severe a punishment for espionage when no war was ongoing and no loss of life had occurred as a direct result of the crime committed by Julius and Ethel Rosenberg. He contended that their actions did not meet the criteria set out in Section 2 of The Espionage Act which stipulates capital punishment only if an act results in death or occurs during wartime, neither condition being met in this case according to him. Furthermore, he criticized how quickly they were executed after their appeal was denied without allowing time for due process or consideration from other legal avenues such as Congress or President Truman who could have commuted their sentence to imprisonment instead.