(1) The grand jury may at all times ask the advice of the judge. Unless advice is asked, the judge may not be present during the sessions of the grand jury.
(2) The prosecutor may at all times appear before the grand jury for the purpose of giving information or advice relative to any matter cognizable by the grand jury and may interrogate witnesses before the grand jury whenever the prosecutor finds it necessary.
(3) Subject to the approval of the district court, the county attorney may employ a special prosecutor, investigators, interpreters, and experts at agreed-upon compensation to be first approved by the court.