 With the outbreak of the American Civil War in 1861, Jeter volunteered for service in the Confederate Army and was made a captain of infantry.After the war, Jeter resumed his law practice and was elected to the South Carolina Senate in 1872 after becoming disenchanted by Radical Republican rule of the state during Reconstruction.He continued to serve in the Senate and became the President Pro Tempore in November 1877 because of the mass resignations of Republicans after their party's defeat in the gubernatorial election of 1876, thereby giving control of the Senate to the Democrats.