Prior to becoming an immigration attorney, Shirley managed a refugee resettlement program in New Hampshire and served as a Presidential Management Fellow in the Bureau of Population, Refugees and Migration at the U.S. Department of State. She lived in several African countries while working for non-governmental organizations serving refugees and displaced people. She also served as a Peace Corps Volunteer in Guinea.

Shirley holds a JD from American University, where she was a Public Interest/Public Service Scholar, and graduated magna cum laude, Order of the Coif. She also holds an MPH from Johns Hopkins University and an AB from Brown University.