S.C. Code Ann. § 23-6-185

Notwithstanding any other provisions of law, enforcement by the State Transport Police Division, of Articles 3 and 5, Chapter 23 of Title 58, shall be funded from the motor carrier registration fees collected by the Department of Motor Vehicles that previously were collected by the Public Service Commission and the Department of Public Safety. Additionally, the State Transport Police is authorized to expend the motor carrier registration fees to build or renovate weigh stations. All unexpended funds from prior years collected pursuant to this section may be retained and carried forward by the department for the same purposes.