North Carolina General Statutes Chapter 163. Elections and Election Laws § 163-90.1. Burden of proof

(a) Challenges shall not be made indiscriminately and may only be made if the challenger knows, suspects or reasonably believes such a person not to be qualified and entitled to vote.

(b) No challenge shall be sustained unless the challenge is substantiated by affirmative proof. In the absence of such proof, the presumption shall be that the voter is properly registered or affiliated.