S.C. Code § 16-17-720
It shall be unlawful for any person other than a duly authorized law enforcement officer to represent to any person that he is a law enforcement officer and, acting upon such representation, to arrest or detain any person, search any building or automobile or in any way impersonate a law enforcement officer or act in accordance with the authority commonly given to such officers. Nothing in this section shall be construed to prohibit a private citizen from making a citizen's arrest in accordance with the laws of this State.
Any person violating the provisions of this section shall be deemed guilty of a misdemeanor and, upon conviction, shall be fined not more than five hundred dollars or imprisoned for not more than one year.
S.C. Code § 16-17-720