(concurring in the result) :
I concur in the result.
In my opinion Article 31(6), Uniform Code of Military Justice, 50 USC § 602, does not require that a warning be given a person called to testify as a witness at a court-martial trial. The witness is not questioned as an accused or one suspected of the commission of an offense in a pretrial investigation directed to that offense, as contemplated by the Article. See: My opinion in United States v. Gibson, 3 USCMA 746, 14 CMR 164.
Unquestionably, a person may not be compelled to incriminate himself. When called as a witness, Headnote 5 he may be uninformed of that right. In such a situation, the Manual provides that “the court should advise an apparently uninformed witness of his right to de-*197dine to make any answer which might tend to incriminate him.” Manual for Courts-Martial, United States, 1951, paragraph 1506, page 284. This provision appears to be precatory, but I need not decide whether it is intended as mandatory or only advisory. Clearly, it requires knowledge by the court of facts which would reasonably show that a question put to a witness calls for an answer which might incriminate him. If no such facts appear, the court’s failure to inform the witness of his right cannot be regarded as invalidating his self-incriminating statements.
The accused made no effort to show that, in fact, he did not know his rights, and that at the time he testified as a witness at the guard’s trial, the court should have known that the question put to him required an incriminating answer. From the record, it appears that the accused was actually aware of the privilege against self-incrimination. Before he appeared as a witness at the guard’s trial, the accused was interviewed by an officer investigating the offense then pending against him. In that interview, the investigating officer read and explained Article 31 to him. Under the circumstances, the accused waived his right when he did not claim it at the time he testified as a witness.