Sobell upon release in 1969

Morton Sobell was a friend of the Rosenbergs and a co-defendant in their trial. Sobell met Julius Rosenberg while attending City College of New York, where he received a degree in engineering. Sobell and his good friend Max Elitcher moved to Washington where they took an apartment together and began working at the Navy Bureau of Ordnance. Sobell attempted to recruit Elitcher to do espionage work.

On June 22, 1950 Sobell fled to Mexico City with his wife Helen, infant son Mark, and Helen's daughter Sydney. Sobell tried to find passage for himself and his family from Mexico to Europe, but without proper passports he was not successful. On August 16, 1950, Sobell and his family were abducted by armed men, taken to the United States border and turned over to the FBI. The FBI arrested him for conspiring with Julius Rosenberg to violate espionage laws. 

Sobell never testified at trial, choosing instead to assert his 5th Amendment privilege. Sobell received a sentence of 30 years imprisonment for his role in the Rosenberg conspiracy. After being released from prison in 1969, Sobell wrote an autobiography, On Doing Time, detailing his experience in the Rosenbergs case. Sobell maintains his innocence to this day, claiming that he fled to Mexico because he had lied about his membership in the Communist Party, and denying any involvement in a spy ring.