N.C. Gen. Stat. § 58-72-35
When oath is made before any judge of the superior court by five respectable citizens of any county within his district that after diligent inquiry made they verily believe that the bond of any officer of such county, which has been accepted by the board of commissioners, is insufficient either in the amount of the penalty or in the ability of the sureties, it is the duty of such judge to cause a notice to be served upon such officer requiring him to appear at some stated time and place and justify his bond by evidence other than that of himself or his sureties. If this evidence so produced fails to satisfy the judge that the bond is sufficient, both in amount and the ability of the sureties, he shall give time to the officer not exceeding 20 days, to give another bond, fixing the amount of the new bond, when there is a deficiency in that particular. And upon failure of the said officer to give a good bond to the satisfaction of the judge within the 20 days, the judge shall declare the office vacant, and if the appointment be with himself, he shall immediately proceed to fill the vacancy; and if not, he shall notify the persons having the appointing power that they may proceed as aforesaid.
N.C. Gen. Stat. § 58-72-35