Here is an interesting piece by Prof. Colin Miller about the judge who asks questions of witnesses. Prof. Colin Miller, I Won't Be The Judge Of That: Texas Appeal Reveals That The Lone Star State Doesn't Allow For Judicial Interrogation, 9 April 2009.
I think that most people would agree that judges should at least be able to ask some questions to witnesses, and as far as I know, Oregon is the only other state [other than Texas] that does not allow for judicial interrogation. But I'm not going to argue with the Texas position because I think that the Lone Star state is correct that judicial questioning can give off the appearance of judicial bias (or show actual judicial bias).
Here are the Military Rules of Evidence.
Mil. R. Evid. 605 states:
(a) The military judge presiding at the court-martial may not testify in that court-martial as a witness. No objection need be made to preserve the point.
(b) This rule does not preclude the military judge from placing on the record matters concerning docketing of the case.
Fed. R. Evid. 605 states:
The judge presiding at the trial may not testify in that trial as a witness. No objection need be made in order to preserve the point.
Mil. R. Evid. 614(b) states:
(b) Interrogation by the court-martial. The military judge or members may interrogate witnesses, whether called by the military judge, the members, or a party. Members shall submit their questions to the military judge in writing . . . When a witness who has not testified previously is called by the military judge or the members, the military judge may conduct the direct examination or may assign the responsibility to counsel for any party.
Fed. R. Evid. 614(b) states:
(b) Interrogation by court. The court may interrogate witnesses, whether called by itself or by a party.
Remember, that under the current rules:
Rule 1102. Amendments Amendments to the Federal Rules of Evidence shall apply to the Military Rules of Evidence 18 months after the effective date of such amendments, unless action to the contrary is taken by the President.