S.C. Const. art. II, § 7
The General Assembly shall establish disqualifications for voting by reason of mental incompetence or conviction of serious crime, and may provide for the removal of such disqualifications. Persons who are confined in any penal institution under the judgment of a court shall not be entitled to vote.
(1970 (56) 2691; 1971 (57) 319.)
The present provisions of this section are somewhat similar to former Section 6 of Article II as it existed prior to the 1971 revision. For similar provisions in Constitution of 1868, see Const 1868, Art VIII, Section 8.