Idaho Code § 19-1105
In the investigation of a charge for the purpose of either presentment or indictment, the grand jury can receive any evidence that is given by witnesses produced and sworn before them except as hereinafter provided, furnished by legal documentary evidence, the deposition of a witness in the cases provided by this code or legally admissible hearsay. No witness whose testimony has been taken and reduced to writing on a preliminary examination must be subpoenaed or required to appear before the grand jury, until such testimony has been first submitted to and considered by the grand jury, but if such testimony has been lost or cannot be found, or if the grand jury after considering the same still desires the presence of any such witnesses, they may be subpoenaed.
Idaho Code § 19-1105