(a) A grand jury:
(1) Must return a bill submitted to it by the prosecutor as a true bill of indictment if it finds from the evidence probable cause for the charge made.
(2) Must return a bill submitted to it by the prosecutor as not a true bill of indictment if it fails to find probable cause for the charge made. Upon returning a bill of indictment as not a true bill, the grand jury may request the prosecutor to submit a bill of indictment as to a lesser included or related offense.
(3) May return the bill to the court with an indication that the grand jury has not been able to act upon it because of the unavailability of witnesses.
(4) May investigate any offense as to which no bill of indictment has been submitted to it by the prosecutor and issue a presentment accusing a named person or named persons with one or more criminal offenses if it has found probable cause for the charges made. An investigation may be initiated upon the concurrence of 12 members of the grand jury itself or upon the request of the presiding or convening judge or the prosecutor.
(5) Must inspect the jail and may inspect other county offices or agencies and must report the results of its inspections to the court.
(b) In proceeding under subsection (a), the grand jury may consider any offense which may be prosecuted in the courts of the county, or in the courts of the superior court district or set of districts as defined in G.S. 7A-41.1 when there has been a waiver of venue in accordance with Article 3 of this Chapter, Venue.
(c) Bills of indictment submitted by the prosecutor to the grand jury, whether found to be true bills or not, must be returned by the foreman of the grand jury to the presiding judge in open court. Presentments must also be returned by the foreman of the grand jury to the presiding judge in open court.
(d) The clerk must keep a permanent record of all matters returned by the grand jury to the judge under the provisions of this section.