Julius and Ethel met in 1936 when Julius became a leader in the Young Communist League. In 1942, Julius and Ethel became full members in the American Communist Party. In early 1945, Julius was fired from his job with the Signal Corps when they learned of his past membership in the Communist Party. On June 17, 1950, Julius Rosenberg was arrested on suspicion of espionage after having been named by Ethel's younger brother, Sgt. David Greenglass, and a former machinist at Los Alamos, who confessed to passing secret information to the USSR through Harry Gold, a courier. Ethel was arrested on August 11, 1950.
The highly controversial Rosenberg's trial began in 1951. From the beginning, the trial attracted a lot of attention from the media, and generated strong responses from observers. Opinions varied from those who believed the Rosenberg's to be clearly guilty, and others who asserted their innocence. During the trial, Greenglass served as the prosecutions primary witness. He stated that Ethel had typed notes containing U.S. nuclear secrets, and that those notes were later turned over to Harry Gold. Gold would then turn them over to Anatoly A. Yakovlev, the Soviet vice consul in New York City. Both Rosenbergs asserted their right to the Fifth Amendment not to incriminate themselves whenever asked about their involvement in the Communist Party.
On March 29, 1951, the Rosenberg's were convicted and sentenced to death under Section 2 of the Espionage Act. The Rosenberg's stoically maintained their innocence throughout the length of the trial and appeals. They were finally executed by the electric chair on June 19, 1953. The judge for their case noted that he held them responsible not only for espionage but also for the deaths of the Korean War, since the information leaked to the Russians was believed to help them develop the A-bomb and stimulate Communist aggression in Korea. Their case has been at the center of the controversy over communism in the United States ever since.
Despite controversy over the sentencing of the Rosenberg's, significant evidence in support of their guilt surfaced in later years, such as Memoir of Nikita Khrushchev. However, in a New York Times editorial published on the 50th anniversary of their execution, "The Rosenberg case still haunts American history, reminding us of the injustice that can be done when a nation gets caught up in hysteria" is written, supporting their innocence. References to the Rosenberg's are still common in pop culture in modern media such as poems, novels, songs, and TV shows.