S.C. Code Ann. § 23-1-15 gives law enforcement officers authority to enforce all traffic laws on parking lots open to use by the public, even though such lots are privately owned. Before such authority may be exercised, the parking lot must be posted "with appropriate signs to inform the public that the area is subject to police jurisdiction with regard to unlawful operation of motor vehicles."
Both State traffic laws and municipal ordinances (when the area is in the city or town) may be enforced under S.C. Code Ann. § 23-1-15, which reads:
Any real property which is used as a parking lot and is open to use by the public for motor vehicle traffic shall be within the police jurisdiction with regard to the unlawful operation of motor vehicles in such parking lot.
Such parking lots shall be posted with appropriate signs to inform the public that the area is subject to police jurisdiction with regard to unlawful operation of motor vehicles. The extension of police jurisdiction to such areas shall not be effective until the signs are posted.
In any such area, the law enforcement agency concerned shall have the authority to enforce all laws or ordinances relating to the unlawful operation of motor vehicles which such agency has with regard to public streets and highways immediately adjoining or connecting to the parking area.
In addition, S.C. Code Ann. § 16-11-760 provides penalties for parking on private property, provided notice prohibiting such parking is posted "in a conspicuous place on the borders of such property". Punishment for this offense is by a fine of not less than twenty-five dollars nor more than one hundred dollars or by imprisonment for a term not exceeding thirty days. This offense may be charged on a uniform traffic ticket.