Julius and Ethel Rosenberg were accused of passing nuclear secrets to the Soviet Union and were convicted of espionage in 1951. They were executed by electric chair at Sing Sing prison in 1953, becoming the first American civilians to be executed for espionage during peacetime. Their prosecution and execution remains controversial, with some arguing they received an unfair trial and were innocent, while others believe they were rightfully convicted of helping the Soviet Union acquire the atomic bomb.