Tillman served as the alderman of the city's 3rd Ward (map) from 1985 until 2007.
A member of the Democratic Party, representing part of the city's South Side in the Chicago City Council.
As an Alderman, Tillman was a strong advocate of reparations for slavery.
In April 2007, Tillman was defeated in a runoff election by challenger Pat Dowell.
Tillman defeated Dowell in 2003.
Prior to her career as an alderman, Tillman was active in the Civil Rights Movement, working for Martin Luther King's Southern Christian Leadership Conference (SCLC) as an activist.
Tillman was known for wearing large hats and has cultivated this image as her trademark.