A person cannot be examined as a witness in the following cases: 1. Superseded by N.D.R.Ev. 501, 502. 2. Superseded by N.D.R.Ev. 501, 505. 3. Superseded by N.D.R.Ev. 501, 503. 4. A public officer cannot be examined as to communications made to the public officer in official confidence when the public interests would suffer by the disclosure.