(a) When the testimony or other information is to be presented to a court of the trial division of the General Court of Justice, the order to the witness to testify or produce other information must be issued by a superior court judge, upon application of the district attorney:
(1) Be in writing and filed with the permanent records of the case; or
(2) If orally made in open court, recorded and transcribed and made a part of the permanent records of the case.
(b) The application may be made whenever, in the judgment of the district attorney, the witness has asserted or is likely to assert the witness's privilege against self-incrimination and the witness's testimony or other information is or will be necessary to the public interest.
(c) In a jury trial the judge must inform the jury of the grant of immunity and the order to testify prior to the testimony of the witness under the grant of immunity. During the charge to the jury, the judge must instruct the jury as in the case of interested witnesses.