N.C. Gen. Stat. § 6-13: Civil actions by the State; joinder of private party.

In all civil actions prosecuted in the name of the State, by an officer duly authorized for that purpose, the State shall be liable for costs in the same cases and to the same extent as private parties. If a private person be joined with the State as plaintiff, he shall be liable in the first instance for the defendant's costs, which shall not be recovered of the State till after execution is issued therefor against such private party and returned unsatisfied. (Code, s. 536; Rev., s. 1259; C.S., s. 1236.)