(concurring).
I concur in Judge Hastings’ opinion. I do wish, however, to say a few words on the subject of the permissible use of prior convictions to impeach defendant as a witness in his own behalf in a criminal case.
In my concurring opinion in United States v. Escobedo referred to by Judge Hastings, I said that I hesitated to agree that there was an established rule in this Circuit which contemplated the use of prior convictions for impeachment purposes “as a mere exercise of discretion.” I thought that this court should not reject out of hand the District of Columbia “rule of thumb” which limited the introduction of evidence of prior convictions to “crimes involving] the element of falsehood.”
The use of the prior convictions for impeachment purposes is to test the credibility of the defendant. It seems clear to me therefore that only those convictions which have a bearing on credibility, such as those involving dishonesty or false statements, should be admitted for the purpose. It may well be that a conviction for an offense involving the element of false statements can be used to impeach the credibility of a defendant who testified at his trial for bank robbery. The reverse would not be true. The bank robbery conviction might have no effect on a defendant’s credibility in a case involving false statements.
I am troubled somewhat by Proposed Rule 609(a) General Rule (1) of the Proposed Rules of Evidence. I do not *574see how a prior conviction that was punishable by death or more than a year in prison per se bears on credibility, except in crimen falsis offenses involving dishonesty or false statements. I am in agreement with General Rule (a) (2)— approving use of in crimen falsi, and (3) — balancing probative value of the evidence of prior conviction against the danger of unfair prejudice, in so far as it refers to (2).
I would not, at least at this time, favor, as Judge Fairchild does, Rule 21 of the Uniform Rules of Evidence.1 I favor the limited discretion rule proposed in Rule 609(a) subject to the objection noted above in the preceding paragraph.
I agree with Judge Hastings, and with Judge Friendly in United States v. Costa, 425 F.2d 950, 954 (2nd Cir. 1969), cert. den. 398 U.S. 938, 90 S.Ct. 1843, 26 L.Ed.2d 272, to the extent that where a pre-trial motion for exclusion of convictions is made, there should be a showing of what the substance of defendant’s testimony would be, e. g., alibi, and what prior convictions the government proposes to use for impeachment if the defendant took the stand. This procedure would enable the district court to determine whether the defendant intended to take the witness stand, whether the nature of his defense is frivolous, whether the government intends to introduce convictions not involving crimen falsi, and whether the prejudicial effect of introducing convictions which do involve crimen falsi outweighs the probative value of that evidence. This procedure would enable a reviewing court to determine the prejudicial effect in the trial resulting from a pre-trial ruling adverse to the defendant.
I think that a pre-trial motion request of a defendant for determination of the question is a more orderly approach to solving the problem than an interruption of the trial. However, this practice might not be suitable where, for example, the judge is to be the trier of fact and a defendant — if he takes the stand —giving the substance of his testimony beforehand might conceivably prejudice him. Also in some cases it may be unnecessary to ask a defendant to state the substance of what he might testify to, as for instance in the case of a seriously stale conviction. It may well be that a pre-trial determination should not be required. There may be cases in which a defendant may not wish or request pretrial determination. He may be reluctant to indicate to the judge what the substance of his testimony would be if he took the stand. In this latter event, of course, the matter would have to be determined by development at the trial.
I agree with Judge Hastings that in the case before us though presented before trial the question was presented abstractly and that the district court did not err in denying defendant’s motion to suppress his twelve year conviction.
. As of September, 1965, the 'Uniform Rules of Evidence had been adopted only in Kansas, Panama Canal Zone, and Virgin Islands.