Opinion for the Court filed by Circuit Judge McGOWAN.
Opinion filed by Circuit Judge MacKINNON, concurring in part and dissenting in part.
Circuit Judges ROBB and WILKEY concur in the result.
McGOWAN, Circuit Judge:
These criminal appeals were made the subject of en banc consideration because they variously involve issues relating to (1) the range of application of 14 D.C. [3]*3Code § 305 and (2) its validity as against constitutional challenge in those cases where it does apply. The statute is addressed to witness impeachment by prior conviction, and it makes such evidence mandatorily admissible in the circumstances specified by it.1
These cases were held in abeyance to await this court’s en banc decision in United States v. Henson, 159 U.S.App.D.C. 32, 486 F.2d 1292 (1973). In Henson the court unanimously determined that 14 D.C.Code § 305 is an ex post facto law when applied to the trial of defendants for crimes allegedly committed pri- or to February 1, 1971, the effective date of the statute. Henson does not govern the instant appeals, however, since all appellants were convicted of offenses committed subsequent to that date. It is thus necessary for the court now to resolve issues not reached in Henson.
We conclude that 14 D.C.Code § 305 is applicable to District Court trials of indictments alleging only violations of the D.C.Code and returned in the District Court during the eighteen-month transitional period (February 1, 1971 to August 1, 1972) established by 11 D.C.Code § 502(2).2 In such case, we also find that the statute is not violative of the United States Constitution. Finally, we hold that, where an indictment is triable in the District Court because it includes both U.S.Code and D.C.Code offenses, the mandate of 14 D.C.Code § 305 is not operative.
I
No. 72-1738—U. S. v. Robinson.
Appellant Robinson was tried on an indictment returned in the District Court prior to August 1, 1972 and alleging only violations of the D.C.Code. He was convicted on two counts of assault with a dangerous weapon (22 D.C.Code § 502), and two counts of armed robbery (22 D.C.Code §§ 2901, 3202).3
The evidence of record indicates that appellant and a companion, one Allen, entered a liquor store, and that Allen produced a pistol. Appellant remained in the middle of the store while Allen stole some $150. At one point an employee entered the store, and appellant instructed him to stand still and keep his [4]*4hands down. Finally, upon completion of the robbery appellant left the store with Allen, who had taken the store owner as hostage. A scuffle ensued between Allen and the hostage, in the course of which Allen took the hostage’s watch, following which both appellant and Allen entered an automobile driven by a third person.
An alert passerby noticed the events outside the store, followed the car, and notified the police. All three occupants were apprehended in the automobile, and the spoils of the robbery were recovered.4
Before taking the stand in his own defense, Robinson asked that the prosecution be barred from impeaching him with a prior conviction for second degree murder. This was denied, apparently by reference to the mandatory nature of the statute. Robinson took the stand anyway, and was impeached over his objection. On appeal, he argues that the application of the statute to him was so prejudicial as to constitute a deprivation of due process.5
Nos. 73—1165, 73—1167—U. S. v. Lewis and Walls.
Appellants in these consolidated appeals, and a third individual named in the indictment, were convicted of robbery, 22 D.C.Code § 2901, and all appealed. The appeal of the third person was dismissed on his own motion, and a division of this court, by an order entered October 4, 1973, affirmed appellants’ convictions without prejudice to their notation of a further appeal if the pending en banc decision in Henson should warrant such action. Appellants having filed for rehearing on the day following the announcement of Henson, the division allowed rehearing and received supplemental briefs from the parties.
Two points were initially urged upon the division. One was that the evidence against Lewis (who testified without impeachment) was insufficient to support his conviction, and that his conviction should be reversed because of the consequent error in denying his motion for acquittal. The other was that the statute mandating the impeachment of Walls by prior convictions for simple assault and petty larceny was unconstitutional — an issue which had not been raised in the District Court and in support of which appellants mainly relied on the briefs before the court en banc in Henson.6
[5]*5Since the principal issues presented by this appeal in its present posture concern the applicability and constitutionality of 14 D.C.Code § 305, we find it unnecessary to elaborate at length the evidence produced at trial. We find, as did the division, that such evidence sufficed to support the conviction of Lewis.7
In their supplemental brief on rehearing, appellants urge two non-constitutional grounds for reversal. The first of these is that, since simple assault is not a felony and does not involve dishonesty or false statement, the trial judge erred in permitting impeachment of Walls by a prior conviction for that offense. The Government concedes the error, as it must in light both of the explicit limiting language of 14 D.C.Code § 305 and the legislative history of that statute, which latter clearly indicates that Congress did not regard “dishonesty or false statement” as comprehending assault. It argues, however, that the error was harmless under all the circumstances, and provides no occasion for the reversal even of Walls’ conviction, much less that of both appellants.8
Appellants’ second non-constitutional claim is that, properly construed, 14 D.C. Code § 305 does not apply to any criminal trials in the District Court, irrespective of whether the offense is federal or local. A contrary reading, they insist, woftld result in a denial of equal protection, since criminal defendants would be tried in the federal courts of the District of Columbia under evidentiary rules differing from those which could be observed in federal courts outside the District, Congress not having as to the latter purported to foreclose the exercise of discretion to determine in appropriate circumstances that the prejudicial effect of a prior conviction outweighs its probative value with respect to credibility.
No. 72—1887—U. S. v. Belt.
Appellant Belt was charged under a two-count indictment alleging violations of (1) the federal offense of possession of narcotics with intent to distribute, 21 U.S.C. § 841, and (2) 33 D.C.Code § 402, which prohibits unlawful possession of narcotic drugs. She was acquitted by a jury of the federal charge, but convicted [6]*6and sentenced for violation of the D.C. Code provision.
The evidence of record indicates that on January 21, 1972, a police officer, pursuant to a valid warrant, entered appellant’s bedroom and questioned her about narcotics. During the questioning, the officer was momentarily distracted by a dog. Shortly thereafter, a second officer arrived at appellant’s bedroom with a packet containing heroin that he said had just been thrown from appellant’s window. Neither officer actually saw appellant throw the packet, and appellant denied that she had done so. During the course of her testimony, appellant was impeached with evidence of a 1963 narcotics conviction. Admission of that evidence followed defense counsel’s objection and a bench conference in which the court indicated its opinion to be that 14 D.C.Code § 305 applied.
In this court appellant asserts that (1) the evidence was insufficient to support her conviction for the local offense of possession and (2) 14 D.C.Code § 305 impaired her rights, under the Fifth and Sixth Amendments, to due process and trial by an impartial jury. As to the former, our examination of the entire record causes us to conclude that the trial court did not err in submitting the matter to the jury.
II
Robinson, and Lewis and Walls, involve indictments charging only D.C. Code offenses. They were tried in the District Court only because the indictments were returned prior to August 1, 1972 — the end of the 18-month transitional period leading to exclusive jurisdiction over such indictments in the Superior Court of the District of Columbia. These cases, thus, present initially the question of whether 14 D.C.Code § 305 was intended by Congress to apply to trials of such indictments in the District Court. If the answer to that question is yes, Belt, which involves an indictment combining U.S.Code and D.C.Code offenses, presents — -by reason of our holding in Hairston that Section 305 does not apply to trials of U.S.Code offenses — the practical problem of whether it governs the single trial of the combined offenses.
As noted above, appellants Lewis and Walls argue the first of these questions in terms of Section 305’s asserted inapplicability to any criminal offense — federal or local — tried in the District Court. Since that argument was first propounded to us, we have, in Hairston, excluded U.S.Code crimes from the statute’s reach. That result, however, does not carry with it a similar conclusion as to the trial of D.C.Code offenses in that court under the transitional jurisdiction.
Hairston turned upon the manifest purpose of Congress, in the sweeping judicial reorganization effected by the District of Columbia Court Reform and Criminal Procedure Act of 1970, 84 Stat. 473, to alter sharply the pattern of the past. As we there said (at 1054 of 495 F.2d):
The intention of Congress in the D.C. judicial reorganization was to create an independent judicial system to be responsible for “local” matters, and to free the federal courts of the District of that responsibility. The jurisdiction of the latter was to be reshaped in a manner more closely paralleling that of the other Article III courts of the nation. . . . Even the most superficial examination of the legislative history of the Court Reform and Criminal Procedure Act reveals that Congress was both aware of the longstanding unique nature of the federal courts of the District of Columbia and intent upon substantial alteration of that status
We also noted (at 1056) that “. the transfer of jurisdiction over D.C. Code crimes from the federal courts to the local courts was achieved in carefully phased steps.” This was to prevent undue strain on the new local court system during its infancy. The heavy volume of D.C.Code indictments made gradual transfer especially necessary in this area of the law; and the scheme followed in this respect, was to retain jurisdiction in the District Court over D.C.Code indictments for the seven most serious felonies, filed between February 1, 1971, the [7]*7effective date of the reorganization law, and August 1, 1972. 11 D.C.Code § 502. Thus it was that the District Court has continued to function temporarily as a local court in respect of such indictments as were returned during this period; and thus it is that Robinson, and Lewis and Walls, were tried in that court.
The considerations giving rise to our holding in Hairston do not control the issue to which we are now speaking. There we said (at 1051 — 2) that to apply Section 305 to U.S.Code offenses
would place criminal defendants prosecuted in the federal courts of the District of Columbia on a different footing from those tried in any other federal circuit, although both classes of defendants may be charged under the same U.S.Code provisions. This treatment of similarly situated persons in a different fashion is fraught with equal protection overtones
The “similarly situated persons” so referred to are, of course, those charged with U.S.Code offenses; and our concern in Hairston was that persons so charged should not be tried in the federal courts of the District of Columbia under different evidentiary rules than they would be subject to if tried for the same offenses in federal courts outside the District.
Appellants insist that the same concept of equal protection, about which we professed concern in Hairston, requires that any criminal defendant tried in the United States District Court for the District of Columbia must receive the same treatment he would get if tried in a federal court elsewhere. The circumstances are not, however, parallel. In the exercise of its power to legislate for the District of Columbia, U.S.Const. Art. I, § 8, cl. 17, Congress has defined certain crimes in the D.C.Code, and has made temporary provision for their trial in the District Court. There is no claim that Congress could not do this.9 All persons charged solely with D.C.Code offenses are tried under the same rules in the District of Columbia. There is, obviously, no forum elsewhere for the trial of such offenses.
The situation is analogous to that which obtains in all of the 50 states, /. e., a person indicted under the criminal laws of a state may be tried in a state court under evidentiary rules different from those employed by the federal courts within that state in the trial of U.S.Code offenses. No one has ever suggested that that violates the Constitution. In any event, for purposes of the exclusive jurisdiction over certain D.C. Code crimes temporarily vested in the District Court here during the transitional period, the District Court is functioning as a “state” court.10 United States [8]*8v. Brown, 157 U.S.App.D.C. 311, 483 F.2d 1314 (1973), upon which appellants’ principal reliance must rest since, unlike United States v. Thompson, 147 U.S.App.D.C. 1, 452 F.2d 1333 (1971), cert. denied, 405 U.S. 998, 92 S.Ct. 1251, 31 L.Ed.2d 467 (1972), it involved a D.C.Code offense, turned not upon equal protection but upon a finding that certain provisions of the Federal Criminal and Appellate Rules superseded the local bail statute. More to the point, and virtually dispositive of appellants’ claim, is United States v. Greene, 160 U.S.App.D.C. 21, 489 F.2d 1145 (1973), cert. denied, October 29, 1974, in which we held that the insanity defense provision of the D.C. Court Reform and Criminal Procedure Act applied to the trial of a D.C.Code offense in the District Court during the transitional period. In Greene we explicitly disallowed an equal protection contention founded upon the fact that U.S. Courts outside the District (which, of course, try only U.S.Code crimes) are not bound by any such rule in the insanity field.
Ill
Having concluded that Section 305 applies to the trial in the District Court of D.C.Code indictments returned before August 1, 1972, we turn to the question of what happens in the case of indictments charging both U.S.Code and D.C.Code offenses.11 The division of this court that decided Hairston exhibited its awareness of this problem, and stated a view as to its proper- solution in these words (n. 13 at 1054 of 495 F.2d):
To the extent that confusion in the conduct of trials may be anticipated in those cases where the United States Attorney uses the authority given him under the reorganization statute to combine local and federal crimes in the same indictment, resulting in their trial together in the United States District Court, it would appear that the federal forum’s evidentiary law would govern impeachment by prior conviction. The United States Attorney is not, of course, bound under the statute to combine local and federal charges, and is, accordingly, under no inescapable necessity to try local crimes under other than local law.
With Belt now presenting the issue to the court en banc, we adopt the approach of the division in Hairston. It is patently not feasible for the District Court to try a defendant, charged with both local and federal offenses, under differing evidentiary rules; and it would be an indefensible imposition upon slender judicial resources to contemplate separate trials for the federal and local counts in such indictments, if indeed the latter approach could be thought to be within the purview of the statutory grant of jurisdiction. Thus, if the United States Attorney elects to combine local offenses with federal, he must do so in the knowledge that the trial will be conducted under federal evidentiary law.
Given our holding in Hairston that 14 D.C.Code § 305 does not apply to the trial of U.S.Code offenses, impeachment by prior conviction in trials of such offenses in the District Court is presently governed by Rule 26 Fed.R.Crim.P. which in relevant part provides that “[T]he admissibility of evidence and the competency and privileges of witnesses shall be governed, except when an act of Congress or these rules otherwise provide, by the principles of the common law as they may be interpreted by the courts of the United States in the light of reason and experience.”12
[9]*9Congress very recently has acted to provide Rules of Evidence for the federal courts; and the law governing impeachment by prior conviction in the trial of U.S.Code offenses, in the District Court for the District of Columbia as in all others, has been definitively prescribed therein. Public Law 93—595, 93rd Cong., 2nd Sess., approved January 15, 1975. Rule 609 provides that the credibility of any witness, including a criminal defendant, may be impeached by proof of a prior conviction but only if the crime (1) was a felony and the court determines that the probative value of the conviction outweighs its prejudicial effect to the defendant, or (2) involved dishonesty or false statement regardless of the punishment.
This final formulation of the impeachment rule was reached in the Conference Committee, whose report makes clear that the discretionary standard is (1) confined in its application to criminal defendants where impeachment “presents a danger of improperly influencing the outcome of the trial by persuading the trier of fact to convict the defendant on the basis of his prior criminal record,” and (2) does not operate in the case of convictions for offenses involving dishonesty or false statement, which are always to be admitted. These latter offenses are, however, narrowly defined by the Conference Committee in these terms:
By the phrase “dishonesty and false statement” the Conference means crimes such as perjury or subornation of perjury, false statement, criminal fraud, embezzlement, or false pretense, or any other offense in the nature of crimen falsi, the commission of which involves some element of deceit, untruthfulness, or falsification bearing on the accused’s propensity to testify truthfully.
H.R.Rep. No. 93-1597, 93rd Cong., 2d Sess., p. 9.
By the terms of the enacting statute, the Federal Rules of Evidence will take effect on July 1, 1975. They will apply to “actions, cases, and proceedings brought after the rules take effect.” They will also apply to “further procedure in actions, cases, and proceedings then pending, except to the extent that application of the rules would not be feasible, or would work injustice, in which event former evidentiary principles apply.”13
[10]*10IV
Before 14 D.C.Code § 305 was cast in its present form, this court was periodically confronted with claims that its predecessor statute, even as construed in Luck and Gordon, was unconstitutional. The argument essentially was that the fair trial concepts embodied in the Fifth and Sixth Amendments were negated by a procedure under which a criminal defendant could testify in his own defense only at the cost of having his prior criminal record made known to the jury. It was urged that, even with the limiting instruction as to the credibility purpose for which that record was admitted, the jury would inevitably tend to equate a prior record with guilt of the pending charge; and this formulation was thought to acquire added force with the Supreme Court’s decision in Bruton v. United States, 391 U.S. 123, 88 S.Ct. 1620, 20 L.Ed.2d 476 (1968).14
In United States v. Bailey, 138 U.S.App.D.C. 242, 426 F.2d 1236 (1970), a division of this court carefully reviewed these claims, finding them not insubstantial but concluding that Spencer v. Texas, 385 U.S. 554, 87 S.Ct. 648, 17 L.Ed.2d 606 (1967), foreclosed their allowance.15 Spencer did not directly involve impeachment by prior conviction, since what was under attack in that case was a Texas statutory procedure under which the jury was, for purposes of an increased sentence for recidivism, informed of a defendant’s criminal record prior to its resolution of his guilt or innocence of the pending charge. The constitutional challenge to this procedure was articulated in a manner very similar to the objections voiced to impeachment by prior conviction; and the Supreme Court, in sustaining the Texas statute, purported to find support for that result in the impeachment analogy. Both the majority opinion of Justice Harlan, and a dissenting opinion by Chief Justice Warren, contained observations about the practice of impeachment by prior conviction which were at odds with any claim of its inherent unconstitutionality.
In reaching the result it did in Spencer, the majority was at some pains to stress the necessity in a federal system of a considerable degree of latitude within the constitutional framework lest there be “a wholly unjustifiable encroachment by this Court upon the constitutional power of States to promulgate their own rules of evidence to try their own state-created crimes in their own state courts . . . ” 385 U.S. at 568-69, 87 S.Ct. at 656. Justice Stewart, concurring specially, said (at p. 569, 87 S.Ct. at p. 656) that “[I]f the Constitution gave me a roving commission to impose upon the criminal courts of Texas my own notions of enlightened policy, I would not join the Court’s opinion. . The question is whether those procedures fall below the minimum level the Fourteenth Amendment will tolerate.”
With the new dispensation brought about in the District of Columbia by the Court Reorganization Act, creating for the first time a relationship between this court and the local courts of the District more nearly like the one obtaining between federal and local courts elsewhere in the country, we cannot be oblivious of considerations of a similar nature. We deal here with an evidentiary rule promulgated by the legislature for the trial of local crimes in the local courts. For the purposes of the cases before us, the [11]*11District Court, as noted hereinbefore, is functioning temporarily as a local court. In this context we must be alert to the admonitions of the Supreme Court against imposing our notions of policy under the guise of constitutional interpretation. In thinking about impeachment by prior conviction, considerations relevant to wise policy, on the one hand, and constitutional requirements, on the other, easily become intermingled, but it is the business of judges to know when the two are. not the same.16
As in the case of the old, the constitutional challenge to the new statute is total. An alternative reason for finding invalidity is, however, now said to be not that any impeachment at all is bad but, rather, that the statute is mandatory, leaving no room for the judge in a particular case to exclude prior conviction evidence because he believes its probative value on credibility to be outweighed by its prejudicial effect. The constitutional argument in these precise terms has heretofore been pressed upon the D.C. Court of Appeals — the “supreme court” of the District of Columbia in the new era ushered in by court reorganization. In Dixon v. United States, 287 A.2d 89 (1972), cert. denied, 407 U.S. 926, 92 S.Ct. 2474, 32 L.Ed.2d 813 (1972), the D.C. Court of Appeals rejected this argument, as well as the earlier formulations of the constitutional claims which we had, in Bailey, found to be barred by the language used in Spencer.
In doing so, the DCCA was obliged to recognize that there are words in the Spencer opinions that may be thought to look the other way. Justice Harlan, in his opinion for the majority, enumerated a number of situations in which evidence of prior crimes is now, and has long been, held to be admissible in criminal trials. The last in his extended series of examples was “when the defendant has testified and the State seeks to impeach his credibility . . ” He went on to say that (at p. 561, 87 S.Ct. at p. 652):
In all these situations . the jury learns of prior crimes committed by the defendant, but the conceded possibility of prejudice is believed to [12]*12be outweighed by the validity of the State’s purpose in permitting introduction of the evidence. The defendants’ interests are protected by limiting instructions . . . and by the discretion residing with the trial judge to limit or forbid the admission of particularly prejudicial evidence even though admissible under an accepted rule of evidence
It is this last clause, of course, that gives rise to the contention that the Supreme Court in Spencer must be taken as having declared that the constitutionality of impeachment by prior conviction depends upon the saving grace of discretion.17 Judge Kern, in his opinion for the DCCA, stated this argument fairly and dealt with it directly. His conclusion was that, when read in the entire context of the majority opinion, this statement could not bear the weight sought to be attributed to it, that is to say, it cannot be characterized as a conscious and purposeful assertion by the Supreme Court that a statute permitting impeachment by prior conviction is bad on its face if it makes no provision in terms for the exercise of discretion.
Our own reading of Spencer coincides with that of Judge Kern.18 In the paragraph of Justice Harlan’s opinion immediately following the language in question, he said as follows (at p. 562, 87 S.Ct. at p. 652):
[13]*13This general survey sufficiently indicates that the law of evidence, which has been chiefly developed by the States, has evolved a set of rules designed to reconcile the possibility that this type of information will have some prejudicial effect with the admitted usefulness it has as a factor to be considered by the jury for any one of a large number of valid purposes To say the United States Constitution is infringed simply because this type of evidence may be prejudicial and limiting instructions inadequate to vitiate prejudicial effects, would make inroads into this entire complex code of state criminal evidentiary law, and would threaten other large areas of trial jurisprudence.
This characterization of his reasoning by analogy from the many instances in which prior crimes evidence is admissible, especially when read in conjunction with his subsequent observations about the duty of the Court to eschew inflexibility in constitutional interpretation where local evidentiary rules are involved, makes it unlikely that Justice Harlan intended, by his generalized reference to judicial discretion, to declare the invalidity of a statute of the kind now before us.
What Spencer does appear to contemplate is that a legislature may, without impingement upon the Constitution, conclude that the public interest in getting before the jury this evidence bearing upon the credibility of the defendant-witness outweighs its inescapably prejudicial effect. A belief that such constitutional latitude exists is reflected in the fact that many states, as in a few federal circuits (note 12 supra), the admissibility of prior convictions for impeachment purposes is treated as a mandatory matter.19
The enactment by Congress of a statute to the same effect for the trial of local crimes in the District of Columbia does not appear to us to be so demonstrably in conflict with the Constitution as to warrant our nullification of the [14]*14choice it reflects in an area of local policy. Such a statute is itself the product of a legislative balancing of the clashing values in having juries possessed of the maximum amount of information relevant to the performance of their essential function, on the one hand, and in minimizing prejudicial effect, on the other. Opinions may differ as to whether, in the case of this statute, the most desirable balance was struck. We do not, however, find anything in Spencer or elsewhere which unmistakably and authoritatively declares or implies that that result is lacking in rationality, or that the Constitution requires the balancing process by which it was reached to be repeated by the judicial branch in each case.20
V
In the light of the foregoing, the convictions appealed from in Nos. 72—1738 (Robinson), and Nos. 73— 1165 and 73—1167 (Lewis and Walls), are- affirmed, with the exception that Robinson’s convictions for assault with a dangerous weapon are vacated.
No. 72-1887 (Belt) presents a more difficult problem. There we have held that trials in the District Court of indictments combining U.S. and D.C.Code offenses are to be conducted under federal evidentiary law. That was not done in this case.21 The transcript indicates that the judge felt, bound to apply the mandatory provisions of 14 D.C.Code § 305. This record does not present a harmless error situation, and normally our response is to remand the case to the District Court with directions to review the admissibility of the prior conviction in the light of the discretion available to the court; if it decides that the prior conviction was admissible in the exercise of a sound discretion, the conviction stands, subject to further review on appeal; if it decides that the prior conviction should have been excluded, the conviction is reversed and a new trial ordered.
It is argued that such a remand is not required here since Belt was acquitted of the U.S.Code offense and, even if the trial court should on remand find reversal necessary, impeachment could be had by the Government at the new trial of the D.C.Code offense. However, the fact remains that, because the prosecutor chose to combine U.S.Code and D.C.Code offenses for trial in a federal court, Belt was entitled to be tried under a rule of evidence that afforded the trial court discretion to exclude impeachment by prior conviction. Full recognition and protection of the integrity of that important procedural right does not admit of its forfeiture by the chance that the jury subsequently elected, for whatever reason, to acquit on the federal charge. The possibility that a second conviction may well result on a retrial, if one is actually ever held, does not alone suffice to deprive this defendant of her entitlement to the court’s reexamination of the admissibility of the prior conviction in the first trial.
Judgment shall be entered in accordance with the foregoing.