N.C. Gen. Stat. § 6-60: No more than two witnesses may be subpoenaed to prove single material fact; liability for fees of such witnesses; one fee for day's attendance.

No district attorney shall direct that more than two witnesses be subpoenaed for the State to prove a single material fact, nor shall the State or defendant in any such prosecution be liable for the fees of more than two witnesses to prove a single material fact, unless the court, upon satisfactory reasons appearing, otherwise directs. And no witness subpoenaed in a criminal action shall be paid by the State for attendance in more than one case for any one day. (1871-2, c. 186; 1879, c. 264; Code, s. 744; Rev., s. 1303; C.S., s. 1284; 1971, c. 269, s. 13; 1973, c. 47, s. 2.)