 Chappell continued the study of law under the tutelage of Augustin Smith Clayton, passed the state bar exam, and became a practicing lawyer.Chappell was elected as to the Georgia Senate in 1832 and 1833 and served in the Georgia House of Representatives from 1834 through 1839.Upon the resignation of Representative-elect John B. Lamar, Chappell was elected as his replacement in the U.S. House of Representatives in 1843 and served in that position until 1845 when he did not seek re-election.