In 1899 she left the SLP and joined the Socialist Party of America (SPA). Malkiel believed that only socialism could liberate women, and that socialism, in turn, could not survive without the full participation of women. In theory, the Socialist party was committed to equal rights for men and women, but in practice, it made no effort to reach out specifically to women workers and showed little interest in their concerns. Malkiel concluded that socialist women would have to fight their own parallel battle for equality.
,br> Malkiel spent the last two decades of her life promoting education for immigrant women and assisting them with naturalization. She founded the Brooklyn Adult Students Association and directed its classes and summer camp.In her later years, Malkiel lent a powerful voice to the movement for women’s suffrage.
Malkiel passed away on November 17, 1949. By then her role as a radical socialist reformer of women’s issues had been largely forgotten. Her obituary described her as the “widow of a well-known New York lawyer”, who had devoted much of her life to education.