S.C. Code § 23-3-170
In any motor vehicle accident involving injury or death of a person where there is cause to believe that an illegal drug or controlled substance was used prior to the accident by any person involved therein, the law enforcement agency having jurisdiction to investigate the accident shall commence a detailed investigation to determine the circumstances under which the illegal drug or controlled substance was obtained.
Upon initiation of this investigation by the local investigating law enforcement agency, the South Carolina Law Enforcement Division shall assist in whatever capacity necessary to fully complete the inquiry and shall cooperate and assist in the prosecution of appropriate criminal charges against any person who provided the illegal drug or controlled substance to that person.
S.C. Code § 23-3-170