Jo Ann Davidson was born on September 28, 1927, in Findlay, Ohio. Upon attaining adulthood, Davidson moved to Reynoldsburg, Ohio, where she raised her family and also embarked upon a political career. She first ran for the Reynoldsburg City Council as a Republican in 1965, but voters elected another candidate. Two years later, Davidson won a seat on the city council. After spending a decade in this position, she won election as the clerk of Truro Township, and in 1980, voters elected her to the Ohio House of Representatives. Davidson served as a representative for the next twenty years, the maximum allowable by law due to term limits.
While in the Ohio House, Davidson took a leadership role. She advocated welfare reform and played a major role in the deregulation of electricity in the state. In 1995, her fellow representatives selected her as the Speaker of the Ohio House. She was the first woman to hold this position and remained as speaker until leaving the House of Representatives in 2001.
Upon stepping down as a representative, Davidson has remained active in various boards and charity organizations. She has served on the board of trustees of The Ohio State University, Franklin University, and the University of Findlay. Over her life, Davidson has also been a member of or assisted the Reynoldsburg Parent-Teacher Association, the Girl Scouts of America, the March of Dimes, the Ohio Chamber of Commerce, and the American Heart Association.