20-12.1. Impaired supervision or instruction.
(a) It is unlawful for a person to serve as a supervising driver under G.S. 20-7(l) or G.S. 20-11 or as an approved instructor under G.S. 20-7(m) in any of the following circumstances:
(1) While under the influence of an impairing substance.
(2) After having consumed sufficient alcohol to have, at any relevant time after the driving, an alcohol concentration of 0.08 or more.
(b) An offense under this section is an implied-consent offense under G.S. 20-16.2.