In 1871, Couzins graduated from Washington University in St. Louis, becoming the first  woman in the United States to graduate from a law school. Establishing a practice in St. Louis, she wrote articles for Elizabeth Stanton and Susan B Anthony's publication, "The Revolution." Then, instead of practicing law, she rose to prominence as a suffragist. Like Stanton and Anthony, she opposed the Fifteenth Amendment. Couzins was described as a riveting orator and lectured across the United States. In 1884, she testified before the U.S. House Judiciary Committee on the legal status of women. In 1887, Couzins became the first female U.S. Marshal in the country.
Couzins died in St. Louis on December 6, 1913 and was buried at Bellefontaine Cemetery.
- "Phoebe Couzins". Missouri Women's Council. Retrieved 2014-06-26.
- New York Times PHOEBE COUZINS DIES AT 72; First Woman Lawyer in United States Succumbs in Poverty.
- "June 15 Events in History". Brainyhistory.com. Retrieved 2014-06-26.
- "Phoebe Couzins (1839?-1913)". Picture History. Retrieved 2014-06-26.
- Nicholson, Ann. "Appleton first Barkeloo-Couzins professor; New chair honors two pioneering women lawyers". Washington University in St. Louis. Retrieved 2014-06-26.
- [dead link]