The grand jury may, at all reasonable times, ask the advice of the court, or the judge thereof, or of the prosecuting attorney; but unless such advice is asked, the judge of the court must not be present during the sessions of the grand jury. The prosecuting attorney of the county may at all times appear before the grand jury for the purpose of giving them information or advice relative to any matter cognizable by them, and may interrogate witnesses before them whenever they or he think it necessary, but no other person is permitted to be present during the sessions of the grand jury, except the members, witnesses actually under examination, an interpreter when necessary, a supporting person for a child witness requested by the prosecuting attorney as authorized by section 19-3023, Idaho Code, and the person designated by the district judge or the presiding juror to report the proceedings, and no person must be permitted to be present during the expressions of their opinions, or giving their votes upon any matter before them.