In September 1951, the FBI notified the General Accounting Office of evidence Moss had been a member of the Communist Party in the mid-1940s, but at that time the army did not reopen the case. This evidence came from Mary Stalcup Markward, who, working as an informant for the FBI, had joined the Communist Party from 1943 to 1949. Markward held such positions as membership director and treasurer for the party. She reported regularly to the FBI, gave them copies of party documents, membership lists, and detailed accounts of meetings and activities. In February 1954, Markward testified before the House Un-American Activities Committee. Although she could not identify Moss personally, she testified that she had seen Annie Lee Moss's name and address on the Communist Party's membership rolls in 1944.