In 1925 she began working with the National Committee of the International Labor Defense in 1927, a communist-led organization that defended labor activists and unjustly-accused African Americans such as the Scottsboro Nine and Angelo Herndon. While it is commonly accepted by nearly all biographical accounts (including those of the Lucy Parsons Center, the IWW, and Joe Knowles) that Parsons joined the Communist Party in 1939, there is some dispute, notably in Gale Ahrens' essay "Lucy Parsons: Mystery Revolutionist, More Dangerous Than A Thousand Rioters", which can be found in the anthology Lucy Parsons: Freedom, Equality, Solidarity. Ahrens also points out, in "Lucy Parsons: Freedom, Equality and Solidarity: Writings and Speeches, 1878 - 1937", that the obituary which the Communist Party had published on her death made no claim that she had been a member.
Parsons continued to give fiery speeches in Chicago's Bughouse Square into her 80s, where she inspired Studs Terkel. One of her last major appearances was at the International Harvester in February 1941.
She died on March 7, 1942, in a house fire. Her lover, George Markstall, died the next day from wounds he received while trying to save her. She was believed to be 89 years old. After her death, police seized her library of over 1,500 books and all of her personal papers. She is buried near her husband at Waldheim Cemetery, near the Haymarket Monument. (now Forest Home Cemetery), in Forest Park, Illinois (then part of the city of Chicago).
The fact that the PSL article is silent on Parsons' merciless and principled critique of lifestyle anarchist and Zinn hero Emma Goldman also speaks volumes. IWW leader William D. Haywood tells the truth about Goldman's role in the class struggle here.
The Marxist Internet Archive's Glossary of People is even more useful than PSL and Wikipedia about the last decades of Parson's life:
During the Haymarket Affair, Lucy became a popular speaker as she toured the country on a campaign for clemency, often fighting police trying to restrict her access to speaking forums. After her husband's execution Lucy would remain involved in revolutionary politics, eventually splitting with the anarchist movement and joining the I.W.W. in 1905. In the 1920's Lucy would begin working with the Communist Party, joining officially in 1939, and was involved on behalf of workers, political prisoners, people of color, and women, including the Scottsboro, Angelo Hearndon and Tom Mooney cases. Lucy would continue to fight against oppression until an accidental fire killed her and her lover in 1942.
Why would PSL not provide a link to their own article about communist work in the US South? In that article there was no Zinn-like silence about the real history we have in that region:
Alabama Communists in the Depression era blazed new ground in organizing the very part of the United States where racist reaction was most entrenched. The movement for sharecroppers' rights and the campaign to free the Scottsboro Boys brought the issues of the rural South to the eyes of millions across the country. This period, almost completely ignored in contemporary histories, saw the Communist Party as among the most influential civil rights organizations in the Deep South.
A 1905 article by Parsons expressing her then-support for anarchism can be heard as an audio file here.