Whenever the membership of a grand jury is reduced in number for any reason, after the grand jury has been impaneled, the judge may direct that the vacancy be filled, and shall so direct if necessary to maintain the minimum number required, in the same manner as the original members were selected. No person selected as a grand juror to fill a vacancy may vote on any matter upon which evidence has been taken prior to the time of the person's selection.
N.D.C.C. § 29-10.1-20