Idaho Code § 19-3112
When a material witness for a defendant, under a criminal charge, is a prisoner in the state prison, or in the county jail of a county other than that in which the defendant is to be tried, his deposition may be taken on behalf of the defendant, in the same manner provided in the case of a witness who is sick, and the provisions of this chapter, so far as applicable, govern in the application for, and in the taking and use of, such deposition. Such deposition may be taken before any magistrate or notary public of the county in which the jail or prison is situated. Every officer before whom testimony is taken by virtue hereof shall have authority to administer, and must administer, an oath to the witness that his testimony shall be the truth, the whole truth, and nothing but the truth.
Idaho Code § 19-3112