SPOTTSWOOD W. ROBINSON, III, Circuit Judge:

Appellants have been found guilty by a jury on numerous charges emanating from two armed robberies in the District of Columbia and the slaying of a police officer as the aftermath of one. On the verdicts, the trial judge entered judgments convicting appellants and sentencing them to long terms of imprisonment. Appellants now tender for our consideration a veritable host of contentions, all of which we have studied assidiously. Finding, in the circumstances of the case, no need for definitive decision of some issues, and no error warranting reversal on the others, we affirm the judgments in part and vacate them in part, leaving unaffected the maximum term of imprisonment imposed.

I. THE FACTUAL BACKGROUND

We start with a summary of the events comprising the offenses with which appellants were charged and the major developments at the trial ensuing. Our recitation is not nearly exhaustive of the innumerable details, nor need it be at this point. Appellants do not dispute the commission or the ingredients of the crimes, or their roles as perpetrators; their points on appeal, rather, are objections to procedural aspects of the trial, and the facts bearing on each are staked out fully as they are successively treated in subsequent sections of this opinion. Our present effort, then, is simply to recount highlights in order to frame the backdrop against which the legal issues posed can more perceptively be analyzed and resolved.

A. The Offenses

The two holdups from which the charges in suit emanated took place on May 24 and 25, 1971. On the first date, at about 11:00 a.m., appellants entered a branch office of the American Savings and Loan Association at 4900 Massachusetts Avenue, N.W. Dressed in business suits and sporting short, conservative haircuts, the two men first conferred briefly. Caldwell then approached teller Betty Vance and asked about opening an account; simultaneously, Timm proceeded to the window of another teller, Gwenda Younger. After a customer in front of Timm completed her transaction, he placed a briefcase on the counter with a note saying, "place your money in this briefcase." Perceiving a dark automatic pistol pointed at her, Ms. Younger reached for bait money, but was foiled when Timm recognized what she was about to do and warned her not to touch the bait money or the alarm. After emptying her own money drawer, she obeyed his order to obtain additional cash from another teller. A total of $4,305 was taken.

Both men fled from the building on foot. Officer Nelson Gosnell, already staking out a nearby bank, observed them as they crossed an adjacent parking lot to an intersection, at which point they separated and casually walked away in different directions. In a matter of minutes, Officer Gosnell responded to the report of the holdup of American Savings, but by that time appellants had escaped and no one was able to track their movements.

On the next morning, May 25, again about 11:00 a. m., the second holdup occurred at a branch of the National Permanent Federal Savings and Loan Association located in a small shopping center on MacArthur Boulevard. Timm, the first to enter, proceeded directly to the window of a teller, Nancy DuTeil, and again used the pretense of inquiring about opening a savings account. Unbeknown to Timm, two police officers, William L. Sigmon and William Schwartz, at the time were stationed in a back room, but, unfortunately, they had no way of watching activity inside the branch.

While Ms. DuTeil was preoccupied with Timm, Caldwell appeared at her window, this time wearing a beard and collar-length hair. As she turned to assist Caldwell at the window, he produced a gun and directed her to put money into a briefcase. Although she readily complied, Caldwell demanded to know "where . . . you keep the big money?" When she informed him that only the vault contained a larger amount, he ordered her to open it.

Her unsuccessful fumbling in the vault room was noticed by the manager, William Garnett, and as he came to investigate he too was ordered at gunpoint to open her teller's vault. At last, he obtained approximately $5,000 in old bills and about $175 in bait money from each of two tellers' drawers. Garnett and Ms. DuTeil were told to stay in the vault room for five minutes and not to set off the alarm, under Timm's threat to shoot people on the street if his orders were not followed.

As soon as the two left the premises, Garnett informed Officers Sigmon and Schwartz, the policemen in the back, that a robbery had taken place. Officer Sigmon thereupon left by the front door, the same exit used by appellants. The felony-murder in this case was soon to follow from the attempted capture of appellants and a shootout which then ensued.

Appellants had walked through a nearby parking lot, but, they turned back and began to run when they heard Officer Sigmon's demand for them to halt. Almost immediately the gunfire began, though it remains uncertain who fired first. Shooting as he ran ahead of Timm, Caldwell headed for a flight of stairs leading to an alley; following Caldwell's progress, Officer Sigmon took cover, crouching down with his left side against a retaining wall. Other law enforcement officers in the vicinity were on the scene by that time, but held their fire for a variety of reasons.

Officer Sigmon was in a position which blocked Timm's escape route. At a pace described as "walking" to "rather fast," Timm approached Officer Sigmon from behind, the officer, facing Caldwell, being unaware of his presence. Timm then shot the officer in the back from a distance noted by witnesses as varying from six inches to four feet. From the wound thus inflicted Officer Sigmon died.

Officer Wade Bishop then opened fire on Timm, but soon was forced to retreat and call for assistance. Timm and Caldwell managed to reach their getaway vehicle, a blue panel truck driven by a young woman later identified as Heidi Ann Fletcher, and the trio escaped before police were able to complete a search of the area. Shortly after noon, however, Officers Marshall Brothers and Wince Clifton spotted the truck. Matching the physical appearance of the driver, Ms. Fletcher, with their lookout description, the officers pursued the truck and stopped it. Ms. Fletcher was removed from the driver's seat, and Timm and Caldwell from the rear. Also found in the truck were items tying the occupants to the National Permanent Savings robbery.

B. The Trial

After various pretrial proceedings consuming several months' time, appellants reached trial. The trial, by a sequestered jury, lasted three weeks. During the first five days the Government presented its case, which involved 52 witnesses and about 120 exhibits.

The Government's proof of the events comprising the offenses on trial was unopposed, and the identifications of Caldwell and Timm as participants were solid and convincing. With respect to the May 25 holdup, Caldwell was singled out both at a lineup and at trial by Ms. DuTeil and Larry Newman, a witness to the gunfight. Timm was similarly identified by Ms. DuTeil and Officer Bishop. As to the May 24 robbery, Officer Gosnell identified Timm in court, as did tellers Younger and Vance. Ms. Younger had previously picked him out of a lineup, and Ms. Vance had made an identification from a photograph of the lineup. Ms. Younger also identified a .45 caliber gun and a briefcase recovered from the getaway truck as the automatic pistol and briefcase used by Timm in the holdup. Photographs made by cameras positioned inside the robbed institutions were introduced to depict the participation of Timm and Caldwell in the holdups.

Although appellants entered the American Savings branch dressed in disguises, the attempt to mask their identities, as we have indicated, did not prove to be a problem for witnesses there. Ms. Wells, the branch manager, picked Caldwell as one of the robbers and testified that a brown wig found in the panel truck corresponded with the length and color of his hair. Ms. Younger stated that a black wig found in the truck matched Timm's hair color and length when he appeared at the branch, and Ms. Vance recognized the sunglasses and dark clip-ons worn by Timm and Caldwell.

There was also a great deal of other evidence directly implicating the two men, including items uncovered by a search of the panel truck and, as well, by a warranted post-arrest search of an apartment occupied by Timm and Ms. Fletcher. The weapons offenses were established in part by defense stipulations as to basic elements such as non-registration and non-possession of gun licenses. A variety of witnesses testified from their expertise in the forensic sciences to provide the technical links to the robberies and the slaying of Officer Sigmon.

Insanity defenses presented by appellants were their only responses to the charges, and here also the judge and jury were presented with an extensive group of lay and expert witnesses. The gist of Timm's defense was that he suffered from acute and long-standing dependency needs, and that this, coupled with Caldwell's great influence over him, brought about his participation in the robberies. In contrast, Caldwell attempted to show that at the time of the offenses he was afflicted with a "conversion hysteria" — a deep-seated complex which allegedly had progressed since childhood and which ultimately led him to seek punishment from other people. The "conversion" aspect, as interpreted by his experts, took the form of lawbreaking in hope of being caught.

Such were the offenses and the trial, viewed in rather broad outline. There were, we have indicated, many other factual developments bearing on the legal issues posed on this appeal. We elaborate on these as separate discussions of the issues are successively reached in this opinion.

II. PRETRIAL PUBLICITY AND SELECTION OF THE JURY

A. Publicity and Claims of Prejudice

Appellants jointly contend that due to widespread publicity surrounding the case they were denied the "impartial jury" guaranteed to them by the Sixth Amendment. They attack both the court's refusal to order a change of venue and its failure to take more stringent measures to reduce the flow of information concerning ongoing developments of the trial.

Initially, appellants charge that a change of venue was necessitated by extensive media coverage that highlighted, among other things, Officer Sigmon's death, appellants' unorthodox life style and various controversies punctuating certain of the pretrial hearings. They specifically assert that the substance of news articles appearing in the press effectively prejudged their guilt. Furthermore, they add, the District Court's acceptance of Heidi Fletcher's plea of guilty prior to trial likewise tended to implicate them. For each of several reasons, we conclude that the trial judge committed no error in finding that there was no such prejudice against appellants that they could not obtain a fair and impartial trial.

The absence of error stems primarily from appellants' failure to properly exploit their opportunities to seek a change in venue and their inability in any event to show actual harm from a trial in the District of Columbia. The record discloses that in June, 1971, not long after his arrest, Timm moved before a United States magistrate for a change of venue because of post-arrest publicity, that the motion was denied without prejudice to renewal before the District Court, and, as will appear, that no suitable effort to renew the motion ever came forth. Six months later, Caldwell moved on another ground for a change of venue, which in our view the court very properly denied. We note additionally that on each of two mornings while selection of a jury was under way, both appellants directed the trial judge's attention to news articles and broadcasts appearing overnight and again moved for a change of venue. On both occasions, the judge specifically denied the request because there was no indication at that point that an impartial jury could not be obtained, and we cannot say that the judge's ruling was wrong. In sum, we find no error in disposing of appellants' several efforts to change the place of trial, when and as those efforts were made.

Neither appellant has convinced us alternatively that the trial judge erred in failing to order sua sponte a severance of defendants followed by a change of venue. As we stated in our opinion in Jones v. Gasch, the critical question on a pretrial motion for change of venue "is whether it is possible to select a fair and impartial jury, and the proper occasion for such a determination is upon the voir dire examination." Throughout the pretrial period in this case, appellants asserted no more than the existence of widespread, uncomplimentary publicity. Where, as here, our examination of the publicity does not enable us to say that a fair and impartial jury was completely unobtainable, that assertion, without more, does "not in itself constitute a sufficient showing of prejudice." As we later conclude, the jury ultimately selected for appellants' trial was untainted by the publicity of which appellants now complain.

Additionally, we reject appellants' claim that the trial judge erroneously omitted to take steps to restrict the spread of information about the case. They argue that the judge should have sealed more of the pleadings, held more proceedings in camera and restricted the prosecution's press statements under rules in vogue in the District Court. Such precautions, they contend, would have mitigated the negative effects of attendant publicity, because many news accounts were constructed from what reporters could glean from open records, courtroom observation and the questioning of anyone who would consent to be interviewed.

On none of these points do we find reversible error. Again, appellants did not avail themselves of their right to move for the kinds of orders which they now contend were essential; and in the only two instances in which requests for in camera proceedings were denied, the judge's actions were a reasonable exercise of discretion. On the first occasion, Timm alone moved the judge to hold in camera the hearing at which Heidi Fletcher was to enter a plea of guilty. Quite properly, the denial of this motion was bottomed upon the need for an atmosphere of openness when an accused waives his or her constitutional right to a trial. The second rejection occurred on Timm's request made orally by appointed counsel for similar treatment for a hearing on a motion to suppress identification evidence. The judge opted for a non-secret proceeding in light of opposition from Timm's retained counsel as well as the refusal of Caldwell's lawyers to adopt any position at all. In spite of the disunity among defense attorneys, the judge nevertheless admonished media representatives not to publish sketches or photographs of appellants just prior to selection of the jury.

We discern no error by the trial judge in not instituting further restriction on disclosures to the press by government personnel. Appellants do complain of news accounts containing remarks attributed to governmental sources. However, we might point out categorically that whatever adverse publicity may have arisen from known Government strategy or opinion could have been materially lessened by timely requests for the sealing of pleadings and the scheduling of non-public arguments. We might also point to the record disclosure that one of Caldwell's counsel made a series of extrajudicial statements to the press, one of which drew a critical admonition from the court; surely, in the context of these facts and in view of his urging that the trial judge should have "restricted the release of information by counsel," he is in no position to complain of publicity for which he is in part responsible.

More importantly, there is a crucial weakness which plagues appellants' claims of error as to the handling of pretrial publicity. Appellants' only defense was insanity, not factual innocence. Thus the requirement of showing prejudice from the publicity complained of became in turn a requirement of demonstrating impairment of the ability or willingness of potential jurors to remain impartial on the insanity issue, and this appellants entirely failed to do. Throughout all of their descriptions and protestations of pretrial press coverage, appellants speak of nothing which does more than reflect on their physical participation in the crimes on trial. The kind of publicity which we are asked to hold prejudicial is easily distinguished from that created when a prosecutor actively seeks a preview in the press of the contest over insanity. Not even inadvertently was that done here. One who seeks to have a federal court set aside a criminal conviction has "the burden of showing essential unfairness . . . not as a matter of speculation but as a demonstrable reality."

B. The Voir Dire Examination

The issues which appellants place before us concerning the selection of the trial jury necessarily flow into their basic contention that they were prejudiced by undue publicity. We are advertent to the principle that voir dire procedures must provide "a full and fair opportunity to expose bias or prejudice on the part of the veniremen," and that "[p]reservation of the opportunity to prove actual bias is a guarantee of a defendant's right to an impartial jury."

Appellants argue first that the trial judge erred in not probing more vigorously the responses of potential jurors as to their exposure to press coverage of the robberies and related offenses. Furthermore, they say, the judge erroneously relied upon the personal assurances of impartiality of certain of the veniremen after only cursory questioning.

Scrutinizing the record, we are satisfied that appellants have no basis for complaining of an inadequate voir dire examination. At no time did attorneys for either appellant tender an objection to the procedure, but we pause briefly to discuss their contentions and decline to find plain error. Their counsel were granted full opportunity to propound their own questions for each potential juror, and the substance of the questions suggested by defense counsel were put to the jury by the judge.

Moreover, in United States v. Robinson we made clear our position on the scope of appellate review of voir dire issues. "Pursuant to Rule 24(a), Fed.R.Crim.P., the trial judge is vested with `broad discretion' in the conduct of voir dire — both as to the mode and manner of proceeding," and we said that so too does this discretion extend to "the range of questions put to prospective jurors." Appellants have not demonstrated that the trial judge abused her discretion. Absent a showing of that, and that their rights were substantially prejudiced, we leave undisturbed the conduct of the voir dire examination.

Caldwell and Timm also challenge the trial judge's reliance on the personal claims of two potential jurors that they could render a fair and impartial verdict on the evidence to be adduced. Both of these individuals, they argue, should have been stricken for cause. Undoubtedly there are occasions upon which further questioning is needed to permit the trial court to make its own judgment of a juror's impartiality based on objective facts, rather than relying exclusively on the jurors' subjective determinations of whether they were prejudiced. But the record before us reveals that the judge proceeded well beyond bare formalities and committed no error in failing to eliminate either of the two persons now subject to appellants' complaint.

Instead of a perfunctory determination of their eligibility to serve, the judge asked followup questions and on the basis of the answers given further evaluated their exposure to pretrial publicity as well as their attitudes on the insanity defense each appellant contemplated. Appellants did not object to the seating of the first challenged venireman, and they successfully prevented the second from serving by use of a preemptory challenge.

Lest we forget, the competence of a citizen to sit on trial juries is to be measured by a common-sense standard. For this and other cases in which similar claims are made, the Supreme Court has prescribed the applicable test:

It is not required . . . that the jurors be totally ignorant of the facts and issues involved. In these days of swift, widespread and diverse methods of communication, an important case can be expected to arouse the interest of the public in the vicinity, and scarcely any of those best qualified to serve as jurors will not have formed some impression or opinion as to the merits of the case. This is particularly true in criminal cases. To hold that the mere existence of any preconceived notion as to guilt or innocence of an accused, without more, is sufficient to rebut the presumption of a prospective juror's impartiality would be to establish an impossible standard. It is sufficient if the juror can lay aside his impression or opinion and render a verdict based on the evidence presented in court.

Our careful study of appellants' objections in light of the record persuades us to the conclusion that here the test was satisfactorily met.

Appellants would also have us find reversible error in the trial judge's failure to strike, sua sponte, for cause an entire class of prospective jurors — policemen's relatives. They urge that the judge was under a duty to eliminate two potential jurors who at that time were closely related to District of Columbia police officers. Alternatively, they insist that the judge should have allotted them additional preemptory challenges to replace three which were used to strike others known to have law enforcement personnel within their families.

In several jurisdictions, the law is established that "[t]he mere fact of membership on a police force is not presumptively a disqualification for service on a jury in a criminal trial." Logically, this premise extends the more so to jury service in a criminal trial by persons who are merely relatives of law enforcement officers.

On its own facts, we are inclined to distinguish this case from claims of prejudice arising from jurors who are former victims of the same type of crime being tried, or a juror who himself was closely associated with a person who has been harmed under the same circumstances as the victim involved in the case on trial. As to the questioned veniremen in the present case, we observe that none was related to a police officer who had been murdered, and no juror who served is shown to have been a victim of or a witness to any offense for which appellants were indicted. We hold that, absent a specific showing of bias, a defendant accused of murdering a police officer is not entitled to a jury free of policemen's relatives.

III. PRETRIAL COMPETENCY DETERMINATION OF CALDWELL

Caldwell urges reversal of his conviction on the ground of insufficient inquiry into his mental competence to continue to stand trial after an apparent attempt to commit suicide. Coupled therewith is his claim that such a significant development rendered invalid findings of competence made at an earlier hearing. He also challenges the trial judge's reliance upon lay testimony at the hearings to support the conclusion that Caldwell was competent.

As in every case wherein the issue arises, we hold fast to the principle that "the conviction of an accused person while he is legally incompetent violates due process." The purpose of a competency hearing is to determine "whether the accused is mentally competent to understand the nature of the charges against him and to assist in his defense." Competence to stand trial requires "sufficient present ability to consult with his lawyer with a reasonable degree of rational understanding — and . . . a rational as well as factual understanding of the proceedings against him." Caldwell's contention suffers because he misinterprets precisely what was at issue at both of his competency hearings.

Retracing his arguments, the only matter to be explored at the second hearing was whether Caldwell's apparent attempt to harm himself seriously rendered him incompetent to further participate in the ongoing trial, not whether he was incompetent in the sense that he was mentally incapable of committing crime at the time the offense on trial occurred. The latter, of course, is the insanity issue to be determined at trial. While one might argue, as Caldwell does, that attempting to destroy oneself signifies a deterioration of one's mental health, this alone does not mean necessarily that the accused is no longer sufficiently cognizant of his role in the trial and able to satisfactorily perform it. In competency hearings, the limitation or expansion of the scope of testimony and the qualifications of participating witnesses lie squarely within the trial judge's discretion. While the proceeding need not be lengthy or involved, "as a minimum we think the inquiry must be of record and both parties must be given the opportunity to examine all witnesses who testify," and the decision on competence must have rational support in the evidence.

In resolving the issue of Caldwell's competence at the second hearing, the trial judge fully complied with these requirements. The judge heard testimony, subjected to cross-examination, from the jail guard who discovered the attempt, and from the doctor and nurse who treated Caldwell. The judge's decision not to alter the original finding was not only procedurally correct, but also amply based on the evidence. A decision as to whether an accused is competent to stand trial is a finding of fact which may not be set aside on appellate review unless it is clearly arbitrary or erroneous, and we certainly cannot say it was either.

Much the same reasoning leads us to conclude that the trial judge's handling of the original competency hearing was without error. In the course of taking both lay and expert testimony, the judge sought to ferret out those rudimentary patterns of voluntary behavior which would indicate whether Caldwell's condition met the criteria for a finding of competence. Upon examination of the record, it is plain that the substance of lay testimony was supportive of Caldwell's awareness of things around him and, as well, his ability to communicate with others. In sum, the evidence was merely contradicted, and the judge found the Government's evidence more persuasive.

IV. RESTRICTIONS ON PRESENTATION OF EVIDENCE

Since appellants offered only the defense of insanity, their complaints concerning the conduct of the trial focus importantly upon the trial judge's regulation of the content of expert testimony on that subject. Both appellants contend that their efforts to prove lack of criminal responsibility for their acts were frustrated by certain of the trial judge's evidentiary rulings. Although we find no prejudicial error, we discuss the arguments seriatim.

A. The Insanity Defense: Caldwell

The first instance of alleged prejudice to the presentation of Caldwell's insanity defense began prior to commencement of the trial and culminated during cross-examination of his witnesses. The court enlisted the aid of various experts to make a pretrial determination of Caldwell's competence to stand trial. The gist of the problem is that the judge denied Caldwell's pretrial motion for an additional examination by a particular psychiatrist, Dr. Leonardo C. Maguigad, whom Caldwell believed possessed "unique" knowledge of his condition. Dr. Maguigad was the admitting psychiatrist when, following arrest, Caldwell was taken to Saint Elizabeths Hospital, and Caldwell points to the anomaly created when the Government sought to impeach another psychiatrist who at trial took the witness stand on his behalf, by highlighting the fact that he had not examined Caldwell until months after commission of the offenses. Caldwell argues that damage to the credibility of his witness and his defense as a whole would not have materialized had the requested appointment been made.

Caldwell's argument is erroneous for more than one reason. The only matter before the court at the time of his request was whether he was competent to stand trial. When the trial court is satisfied that it can resolve the issue of competence without additional appointments, we cannot construe the failure to do so as a denial of expert assistance for a substantive defense of insanity. We emphasize the distinction between appointment of psychiatrists to aid the presentation of an insanity defense and such an appointment to assist the court in determining competence to stand trial. We stressed that distinction in a prior case:

The purpose and nature of [an] appointment [under the Criminal Justice Act] is entirely different from an examination conducted by an order of the court. The latter is conducted to serve the court in a completely nonpartisan manner. While the opinions of such an expert may assist one side or the other in a case, this is not the primary purpose for the expert's appointment. The expert appointed under [the Act], however, is not originally and primarily an aid to the court, but rather is intended to serve the interest of the defendant.

Equally pertinent to the dispute is the fact that Caldwell never informed the judge precisely what constituted the "unique" knowledge in which he was so interested. While a judge would normally choose to appoint impartial psychiatrists to render service to the court itself, the judge cannot be expected to appoint one who is sought after by a defendant, particularly without a specific showing of why no other can perform adequately.

Beyond these considerations, there is another major flaw in Caldwell's current argument. The complaint is that, because Dr. Maguigad was not appointed additionally as an examining psychiatrist for purposes of the competency determination, Caldwell suffered from the lack of Dr. Maguigad's testimony at the trial. This reasoning simply does not withstand scrutiny. On the one hand, the psychiatrist's service at the pretrial stage was no assurance of further service at the trial stage. On the other hand, despite nonappointment earlier, the psychiatrist was appointable and callable at trial. In other words, his availability as a defense witness at trial was in no way dependent upon prior participation in the case. From aught that appears, Dr. Maguigad was absent from the trial simply because Caldwell did not seek to have him there.

Quite apart from the foregoing contention, Caldwell sets forth the additional claim that the prosecution, in violation of a discovery order, withheld statements made and subsequently used them to cross-examine Dr. Alec Whyte, the only expert, among several whom the court appointed for Timm, who testified at trial in support of his insanity defense. More specifically, the Government confronted Dr. Whyte with a letter and a note written by Caldwell while he was allegedly in an unresponsive and uncommunicative state in jail. The object of the cross-examination was to contradict Dr. Whyte's opinion by a showing that the correspondence was a plea by Caldwell to friends for drugs, to be consumed in an attempt to feign mental illness. The letter and note were given to the prosecution by another inmate, Shannon, and were eventually introduced into evidence through Shannon's testimony during rebuttal.

Our task would be simpler if we had before us a complaint involving material ordinarily discoverable under the Federal Criminal Rules, such as a confession, a defendant's grand jury testimony, or a summary of his incriminating conversation with a governmental agent. But what we are called upon to decide is whether Caldwell was entitled to production of personal correspondence not addressed to the Government or intended for its view.

The decision on this question must turn upon whether Caldwell's letter and note were "statements" of the type contemplated by Criminal Rule 16(a), and as such discoverable under the terms of that provision. The Government contends that the language of Rule 16(a) evinces a focus on direct communications between an accused and the Government, and not upon those to third persons which a thorough investigation happens to uncover. Furthermore, the Government reminds, the papers in question were not used as part of its effort to prove Caldwell's criminal culpability, but were held for potential impeachment of defense witnesses on the insanity issue.

We find the Government's position unacceptable. The courts have rejected arguments that the "statements" discoverable under Rule 16(a) are only those made to governmental agents, and that, we think, is as it should be. The rule requires unqualifiedly the production of "written or recorded statements or confessions made by the defendant, or copies thereof within the possession, custody or control of the government . . .," and we are unable to detect in this language the limitation the Government suggests. We believe, too, that acceptance of the language for just what it says is dictated by the fundamental fairness of granting the accused equal access to his own words, no matter how the Government came by them. The point is well illustrated by the instant case, wherein a coherent writing by Caldwell could have had upon the jury the net effect of a written confession of mental soundness. This case also demonstrates that the Government's attempted distinction between substantive and impeachment uses of discoverable material is untenable. Since the court's production order referred clearly and specifically to "all written . . statements made by the defendants," nonproduction of the letter and note violated its terms.

Still, we must determine whether the use the Government made of the correspondence at trial was prejudicial, for if not the nonproduction cannot affect Caldwell's conviction. Caldwell pictures himself as a victim of a mid-trial ambush by the allegedly abrupt reference to the letter and note during Dr. Whyte's cross-examination, but the claim of surprise is negated by the record. Caldwell's counsel was already on notice of the existence of these communications from much-earlier reference to them at the pretrial competency hearing. Neither then nor later did Caldwell request leave to inspect or copy the materials, despite their potential for further use by the Government. In these circumstances, we see no prejudice to Caldwell from their nonproduction in response to the court's order.

B. The Insanity Defense: Timm

Presenting his insanity defense in turn, Timm utilized testimony by a clinical psychologist, Dr. Carl Bauer. On the witness stand Dr. Bauer set forth his observations of Timm's mental condition as deduced from a battery of psychological tests administered by him. In an effort to forestall objection to a crucial part of the testimony, Timm's counsel proffered at the bench that if asked whether Timm could control his behavior on the dates of the two robberies, Dr. Bauer would answer in the negative. According to the witness, that was due partly to extreme dependency needs which rendered Timm easily susceptible to the influence and leadership of others. Counsel thereupon sought a ruling as to whether Dr. Bauer would be permitted to express the opinion that Caldwell's influence over Timm, in the context of the latter's mental illness, led to his participation in the offenses on trial. The issue at hand is whether the trial judge, in light of objections from counsel both for Caldwell and the Government committed reversible error in sustaining the objection to that testimony.

Our starting point is our decision in Jenkins v. United States, in which we held that

[t]he determination of a psychologist's competence to render an expert opinion based on his findings as to the presence or absence of mental disease or defect must depend upon the nature and extent of his knowledge. It does not depend upon his claim to the title "psychologist." And that determination, after hearing, must be left in each case to the traditional discretion of the trial court subject to appellate review. . . . When completion of [graduate] training is followed by actual experience in the treatment and diagnosis of disease in association with psychiatrists or neurologists, the opinion of the psychologist may properly be received in evidence.

Basically, Timm argues that the judge's decision to prohibit the sought-after testimony "was not based upon an analysis of his particular qualifications," as directed by Jenkins, "but on a belief that such questions were `psychiatric questions' and thus could not be answered by a psychologist."

Terming the ruling "arbitrary and erroneous," Timm contends that he was prejudiced because the heart of his defense was never heard by the jury. Timm rightly criticizes the judge's narrowing of the testimony because of a mistaken belief that such an opinion could be expressed only by a psychiatrist. Were this the only justification offered for the ruling, such an approach would have been vulnerable in the absence of a finding that the psychologist's particular qualifications were inadequate support for the testimony in question. Without some other sound basis for excluding the testimony, it would have been error for the judge to have "disregarded Jenkins and turned the hearing into an inquiry into any psychologist's competence to make informed observations about [Timm] without medical training."

From an examination of the record, however, we discern adequate support for the judge's ruling. Phrased most simply, Dr. Bauer had already testified to the outer limit of the factual basis for any opinion he might express. He could not properly have been permitted to proceed beyond the parameters of what he actually knew about Timm. Nowhere in the record is there to be found any suggestion that Dr. Bauer had examined Timm in regard to his relationship with Caldwell. Never was there any claim that Dr. Bauer had been informed that, in point of fact, Timm was influenced by someone else to participate in the crimes charged. The proffer at the bench was far too generalized to allow the judge to draw the conclusion that the witness possessed any such information.

The test for admitting expert opinion is whether it will appreciably aid the trier of fact in determining the factual issues. Application of the test to a particular witness is committed to the broad discretion of the trial judge, whose ruling will not be overturned on appeal unless clearly erroneous. Without knowledge somehow derived that Caldwell exerted influence over Timm in relation to commission of the crimes charged, Dr. Bauer had no factual basis for an opinion of the kind sought, and we uphold its exclusion.

Another contention by Timm in this area is that the trial judge erred in upholding Heidi Fletcher's assertion of her Fifth Amendment privilege against self-incrimination when called to testify on Timm's behalf. Having been sentenced on a plea of guilty to all counts of an indictment for the May 25 robbery, she appeared at the trial in response to a subpoena issued by Timm, who wished to solicit her observations of his personal habits and behavior during the period surrounding the offenses. When direct examination commenced, however, she refused to answer any questions whatsoever. Defense counsel urged the trial judge to disallow the claim of privilege, arguing that she was no longer in any danger of self-incrimination because of the plea and sentence. The Government countered with the explanation that reasonable cross-examination would necessarily and pertinently probe her whereabouts as well as her observations on the days immediately preceding the May 25 holdup of the National Permanent Federal Savings branch, and surely would encompass May 24, the date of the American Savings branch holdup, and May 21, the date of another robbery which the Government believed Timm, Caldwell and Ms. Fletcher had perpetrated.

To successfully invoke the Fifth Amendment privilege against self-incrimination, the danger of incrimination "must be real and appreciable . . . not a danger of an imaginary and unsubstantial character . . . ." We believe that Ms. Fletcher's claim met that standard. There was a substantial possibility that even her indirect comments could have revealed information bolstering any effort by the Government to build a case against her for the May 21 and 24 crimes. That, indeed, was openly acknowledged by counsel who represented her for purposes of her appearance at the trial.

We think that to invoke the privilege it was not necessary as a precondition to assertion of the privilege, for Ms. Fletcher to demonstrate that she would have been forced to admit guilty, or that incidental parts of her testimony would have sealed a future conviction. As the Supreme Court has stressed:

The privilege afforded not only extends to answers that would in themselves support a conviction . . . but likewise embraces those which would furnish a link in the chain of evidence needed to prosecute the claimant . . . . To sustain the privilege, it need only be evident from the implication of the question, in the setting in which it is asked, that a responsive answer to the question or an explanation of why it cannot be answered might be dangerous because injurious disclosure could result.

In the circumstances here, "we cannot say that the possibility of further incrimination was so remote as to deprive appellant of [her] fifth amendment rights."

V. SEVERANCE OF CO-DEFENDANTS

Not surprisingly, the issue of severance emerges from arguments of both appellants. They outline three principal reasons urging reversal. In none do we find error requiring us to disturb their convictions. Appellants simply do not meet the standards we enunciated in United States v. Robinson, that the movant or appellant

must show more than the fact that co-defendants whose strategies were generally antagonistic were tried together. . . At the very least, it must be demonstrated that a conflict is so prejudicial that differences are irreconcilable and `that the jury will unjustifiably infer that this conflict alone demonstrates that both are guilty.'

The first point raised in this regard concerns the presentation of Timm's insanity defense. Timm called as witnesses Dr. Jonas Rappeport and Dr. Leonardo C. Maguigad, both of whom were expected to testify that Timm's criminal acts resulted in part from Caldwell's influence. The trial judge refused to let either expert refer specifically to Caldwell as the person responsible supposedly for Timm's participation in the robberies. Just as he characterized the judge's ruling with respect to Dr. Bauer, here too does Timm claim that he was deprived of vital testimony.

We analyze the issue in two steps: first, whether the trial judge improperly restricted this testimony, and second, whether the judge thereupon committed reversible error in deciding to continue the trial without severing the two defendants. We answer both questions in the negative.

Once again we see an attempt to offer conclusory expert testimony that has no apparent factual basis. This court has previously held that a psychiatric opinion offered in evidence must have a factual predicate. Thus the fundamental question here is how much either expert actually knew about the relationship between Caldwell and Timm. As to Dr. Rappeport, the only information upon which he drew any conclusion about appellants' relationship was a letter, written to the prosecutor by one Monroe Cooper, purporting to describe Caldwell. Cooper had not seen Caldwell at all for many months prior to the robberies, and had only slight contact with him the year before their last encounter. Equally damaging to Timm's contention are Dr. Rappeport's own words, at the bench:

[S]ome of my final conclusions . . . are based on my feeling that Mr. Caldwell had the capability from the little I know or that Mr. Timm may have been influenced unfavorably by someone else and may have been influenced to do this and on the basis of one letter that I have, there seems to be some indication that Mr. Caldwell is the type of person who is quite capable of influencing him. (emphasis added).

We are convinced that as a matter of law there was an insufficient factual basis for this witness' potential testimony. Of particular importance is the fact that Dr. Rappeport had ever examined Caldwell, and the further fact that he had never personally interviewed Cooper. Clinical experiences of that sort might have bolstered measurably any conclusions about Caldwell's effect on Timm. Of like significance, as the trial judge reasoned, is the consideration that the introduction of the letter into evidence for the truth of the descriptions contained in it — as a foundation for the witness' opinion — was forbidden as an admission of hearsay.

Where Timm's second witness, Dr. Maguigad, is concerned, a similar deficiency unfolded at trial. He admitted in testimony that his total contact with Caldwell was only for approximately ten minutes; in his interview with Timm, there was virtually no discussion of Caldwell. For reasons just articulated, we uphold the exclusion of his opinion as to Caldwell's sway over Timm. But as with respect to Dr. Rappeport, we are left with the impression that Timm did receive appreciable benefit from the restricted testimony of Dr. Maguigad. He was, for example, able to describe Timm's bouts with "schizophrenia," "depersonalization" and "dependence" and to conclude that "it is this dependency need that led him to be involved in this situation of robbery."

Timm now contends that the restriction on this line of testimony, assertedly necessary also to protect Caldwell's rights, prevented him from presenting his full defense. Therefore, he argues, the court should have granted his motion for severance. This motion was tendered to the court in mid-trial, at the bench during the conference on Dr. Rappeport, and such tardiness gives us pause: We cannot ignore the fact that, long before the convening of trial, counsel for both appellants knew the nature of their respective defenses. To enable the court to deal effectively with problems arising from conflicting defenses, motions for severance should be tendered at a time sufficiently early to allow a reasonable opportunity therefor.

Without equivocation, we have held that

[t]he decision to grant a severance of defendants properly joined for trial is one over which the trial court possesses great discretion and exercise of that discretion will be reversed on appeal only when it is shown to have been clearly abused. The general rule is that defendants charged with jointly committing a criminal offense are to be jointly tried.

This general rule finds justification in a number of considerations. The joint trial

`expedites the administration of justice, reduces the congestion of trial dockets, conserves judicial time, lessens the burden upon citizens who must sacrifice both time and money to serve upon juries, and avoids the necessity of recalling witnesses who would otherwise be called upon to testify only once.'

The essence of the trial judge's duty on a motion for severance is to determine whether the alleged antagonism between codefendants is "counter productive to the normal reasons for trying the cases jointly."

The denial of the severance motion in the case at bar was not an abuse of discretion. A variety of factors had to be weighed in determining whether Timm and Caldwell should remain together in a single trial until the very end. The trial had already begun, after many months of hearings, examinations, witness-interviews and preparations by the court as well as by the lawyers involved. Potential jurors for any future retrials had been exposed to whatever news coverage ensued after sequestration of the original jury. Moreover, despite the lack of coordination between the two codefendants, their witnesses were able to make their basic positions clear to the jury. In light of appellants' contentions that they suffered from pretrial publicity, an even louder cry of prejudice might have resulted from the coverage of such a dramatic turn of events as mid-trial severance. Taking into account the overall considerations of judicial economy, we cannot say that the trial judge abused her discretion.

The second reason for severance, urged by both appellants, is that the case was too complex for the jurors to understand because of two insanity defenses and varying psychiatric explanations. Additionally, appellants assert that the presentation of the evidence was overly fragmented, and that the Government's rebuttal did not sufficiently distinguish between the two appellants.

This issue was raised at trial only once, when the judge denied a request for a cautionary instruction during the Government's rebuttal, stating her intention to so instruct at the close of trial. At that time the jurors were admonished that they were to determine guilt, innocence, or lack of guilt by reason of insanity as to each defendant separately, and that evidence admitted solely as to one defendant could not be considered against the other. This instruction was one of the last given to the jurors just prior to the beginning of their deliberations. Neither appellant objected or requested any amplification of the charge. Consequently, plain error affecting substantial rights of the parties not being apparent, we do not consider the point. We would in any event be hard pressed to find this a poorly-presented or abnormally complicated case, untriable by a District of Columbia jury.

In their final arguments demanding reversal on account of insanity-related rulings, each appellant claims that the conduct of the other cast doubts upon the genuineness of his insanity defense. Caldwell points to Timm's verbal interruptions of the proceedings; and Timm cites Caldwell's "trance" during various periods of trial, particularly during the Government's rebuttal. So far as Caldwell's actions are concerned, we are cited to no specific facts tending to show that his strange behavior worked to the detriment of Timm. All we are told by counsel is that "[i]f the jurors concluded from their observations of Caldwell during the remainder of the trial that his defense was a sham[,] [t]hey might well have been misled into believing that Timm's defense also was insubstantial." We are not at liberty to upset otherwise valid verdicts on bald speculation.

Caldwell likewise claims that the jury could have viewed him as a malingerer because of Timm's yelling and verbal remarks at the prosecutor and at various witnesses. But here again Caldwell fails to set forth anything to show how these occurrences, without more, damaged his defense, and we cannot hold without an adequate factual basis that there was a carryover effect. Timm's behavior in the courtroom was not beyond the bounds of what might reasonably be expected at a trial of any defendant seeking to persuade the jury that he is mentally unbalanced. To win severance, a codefendant "must show that substantial prejudice derives from the joint trial and not merely that he would have had a better chance of acquittal were he tried separately."

VI. THE PROSECUTOR'S SUMMATION

Appellants have articulated several complaints about the prosecutor's closing argument, charging him with "belittling" their expert witnesses and improperly characterizing the insanity defenses. Our scrutiny of what was actually said, in proper context, unearths no error as to verbal remarks or prosecutorial behavior.

A. Closing Argument Regarding Caldwell

Under the canopy of "belittling" expert witnesses, Caldwell describes two instances in which government counsel allegedly ridiculed testimony by Dr. Whyte, a witness for Caldwell, without any foundation for criticism. First, the prosecutor recalled for the jurors Dr. Whyte's response to a question as to whether he still believed that Caldwell was in his conversion hysteria despite his seemingly normal behavior at the jail. Dr. Whyte's answer, which he later admitted "was a bit flip," was that his diagnosis would remain unaltered even if Caldwell "sat down and wrote a novel." Dr. Whyte sought to emphasize that isolated incidents of voluntary behavior were in his professional opinion, not necessarily inconsistent with a diagnosis of conversion hysteria. Caldwell decries the prosecutor's focus on this one remark, during final argument to the jury, as a basis for challenging the whole of Dr. Whyte's testimony.

Similar criticism is leveled against the Government's repetition of the view expressed by Dr. Whyte as to the significance of the letter written by Caldwell in which he asked his friends for drugs. Without repeating our earlier description of the content of that correspondence, we note Dr. Whyte's conclusion that it indicated that Caldwell wanted to be found sane. The prosecutor attacked this opinion, saying that "from a psychiatrist who presumably understands the English language" the conclusion drawn was "absurd" and "totally undermine[s] the very basis of his testimony."

Caldwell attacks this prosecutorial approach as "inconsistent with the very concept of psychiatry, whose function is to explore the hidden meanings of human behavior." "The statements," he says "amount to an attack on any defense grounded in this science." He continues, "there was no showing by the Government either that Dr. Whyte had `misconstrued' the letter or that he did not understand the English language." Caldwell believes that, in view of the testimony as rendered, the Government had no basis for the "extreme" suggestion to the jury that there was "no evidence to support the fact that he . . . [was] in a conversion hysteria."

It is clear that the prosecution struck hard blows but not foul ones. Just as any vigilant advocate would be expected to do, government counsel merely capitalized on apparent weaknesses in the testimony. In regard to the diagnosis of conversion hysteria, as a tactical matter the prosecutor seized upon what arguably might not make sense to a jury of lay people. With respect to the letter, the prosecutor merely expressed the Government's position that the most reasonable interpretation of its contents was that Caldwell was attempting to secure drugs to induce an abnormal mental state, knowing that a psychiatrist's diagnosis of insanity would be most advantageous. The prosecutor in no way acted unfairly by espousing the more literal of two possible meanings of the writing; that was a classic subject for argument. The Government and the defense were diametrically opposed as to the interpretation of Caldwell's ambiguous message, as Dr. Whyte himself observed, "the content of the letter from the psychiatric point of view has to be evaluated like anything else. It may mean what it says and may mean something quite different."

We may similarly dispose of Caldwell's contention that there was no showing that Dr. Whyte's construction of the letter was erroneous. Whether argument to the jury fully coincides with the evidence is a matter to be decided by the jury as part of the process of determining innocence or guilt. This factfinding process in turn is to be guided by the jurors' personal recollections of the proof. Thus, in the instant case, the mere use in summation of such criticisms as "absurd," without an accompanying recitation of the allegedly supporting evidence, was a characterization that counsel could properly urge, and which the jury could accept or disregard as it saw fit.

The episode in which the prosecutor labeled Caldwell's defense a fraud involved a series of remarks, generally that it was "a big fake of a desperate person who has no other conceivable defense." Caldwell argues that such comments to the jury were inflammatory and prejudicial, because Caldwell's expert witness testified that he had considered and rejected the possibility of malingering and that he ultimately concluded that Caldwell really was mentally ill. We say unhesitatingly that a prosecutor is not precluded from challenging the genuineness of an insanity claim simply because a defense witness has himself rejected the view that the defense is feigned. Our adversary system of conducting criminal trials encompasses no device whereby the accused is forever insulated from attack by offering a witness whose opinion undertakes to refute facts and circumstances in evidence which support a contrary theory of the case.

Here the prosecution's argument did not lack evidentiary support. Caldwell's defense of insanity was called into question, not for the first time in summation, but much earlier during the trial itself. That was accomplished partly through the testimony of a fellow inmate at the jail, who pictured Caldwell as behaving normally, as well as by circumstances such as the letter and the note Caldwell endeavored to send to his friends. Having determined that the argument complained of was not without adequate basis in the record, we lay aside Caldwell's averment that the prosecutor impermissibly expressed personal views on the issue and argued facts not in evidence.

B. Closing Argument Regarding Timm

Timm's first accusation is that the prosecutor misstated the conclusions of Dr. Bauer in summarizing his testimony during his final argument. The alleged misstatement concerned Dr. Bauer's comments on Timm's malingering. When asked whether he had found evidence of faking or manipulation of test results on Timm's part, Dr. Bauer answered in the affirmative. He then tempered his reply with the explanation that malingering is seen "in all patients to some extent," and "stems to a great measure from both emotional fear and despondency, as well as to confusion as to what is actually happening." Referring to Timm, he described it as "beautifully poorly done." In his closing argument, Government counsel urged that this testimony, even as modified, was a significant detraction from Dr. Bauer's ultimate finding that Timm suffered from mental illness.

We are not persuaded that such argument was impermissible. In truth, there was some evidence of malingering, and it was for the jury to decide what if any weight would be attached to it. The trial judge fully appreciated the possibility that some testimony might have been referred to out of context; and she prudently instructed the jurors that counsels' summations were intended to include only what they deemed deserving of special attention, and that the jurors' recollection of the evidence, not counsels' was controlling.

Another line of witness-questioning was also reiterated by the prosecutor in closing argument. During the course of administering a number of psychological examinations, Dr. Bauer employed what is colloquially known as the "house-tree-person" test. Basically, it consists of directing the patient to draw each of those three figures and inferring therefrom his feelings about himself and society. Based on this examination and others, Dr. Bauer concluded that Timm was suffering from a mental disease. Quite candidly, Dr. Bauer stated:

I would not wish the Court to think that on the basis of that drawing in itself I would draw any conclusion of any consequence.

It is one of the blocks in the information which I have gathered. It is significant in that it does correlate with all the other information.

The prosecutor, however, attempted to condense Dr. Bauer's entire testimony, saying "[a]nd yet, according to him, because Timm drew a figure like this, Timm is mentally ill."

Caldwell now contends that the essence of this witness' testimony was distilled by the prosecutor to such a form that it placed disproportionate emphasis upon one of the psychological examinations. We believe, however, that the prosecutor's argument did not provide that much of a twist. While the prosecutor's language was somewhat exaggerated, and while several steps in Dr. Bauer's process of deduction were omitted, nevertheless the statement by government counsel appeared to be little more than an expression of the net result of Dr. Bauer's examinations.

There is a third point which by our assessment is no more substantial in nature. According to the prosecutor's summation, the only examination from which Dr. Bauer found evidence of Timm's dependency needs was the handwriting or graphology test. The accuracy of the prosecutor's statement is not perfect, for Dr. Bauer noted in testimony that dependency was a "theme" which was "consistent throughout the interviews and tests. . ." The graphology test was, however, the only examination from which he concluded specifically that Timm suffered from "arrested dependency needs." We deem the variation innocuous.

Lastly, we are urged to find reversible error in what is viewed as an attempt to use evidence admitted only as to Caldwell to rebut the insanity defense advanced by Timm. To recapitulate the pertinent testimony, Dr. John R. Cavanaugh was called to the witness stand by the Government during rebuttal. At one point he replied to the prosecutor on direct examination "that the quiet, calm, peaceful attitudes of the individuals on the various occasions that you have described, are incompatible with mental illness." The trial judge responded favorably to defense counsel's prompt objection that Dr. Cavanaugh had never examined Timm, and that therefore this testimony should not be allowed to refer to him. Counsel was then permitted to have Dr. Cavanaugh acknowledge that fact before the jury. Despite this, and the judge's ruling sustaining the objection, the prosecutor queried during his closing argument, "although [Dr. Cavanaugh] examined only the defendant Caldwell and his testimony related to him directly, does not what he said apply, in effect, to both?" The judge overruled an objection to this second reference to Dr. Cavanaugh's testimony because the jury had already been informed that he had only examined Caldwell.

In light of the court's ruling on the initial objection, permitting the reference to both individuals was error. But we are mindful of several other items which in any event save the prosecutor's comments from being more than harmless error. Dr. Cavanaugh was not attempting, at the time of his remark, to present a psychiatric diagnosis of Timm, but merely a categorical observation which might well have been rested upon evidence already adduced. Nothing the observation assumed with respect to Timm was a fact not in evidence; the testimony itself, we repeat, was already admitted into the record as to Caldwell. The prosecutor's statement was pure argument, not a factual account or the recitation of a phantom medical opinion.

In sum, our review of these aspects of the Government's summation shows that essentially they were direct appeals to the common sense of the jurors. Contrastingly, we find no indication that they approached a "know-nothing appeal to ignorance." In them we perceive no basis for upsetting the verdicts.

VII. INSTRUCTIONS TO THE JURY

According to both appellants, the trial judge erred in fashioning instructions for the jurors in each of three different areas of the litigation. The first two complaints involve the denial of requested instructions on specific aspects of the case; the last is more realistically an argument against the assignment to appellants of the burden of providing the insanity defenses they sought to erect.

Caldwell submitted to the judge a proposed instruction on second degree murder which stated that, if he were convicted, the punishment would be "up to life, or not less than twenty years." The judge declined to employ such a statement in the charge to the jury. Addressing its more obvious shortcoming, the Government points out that the request, as so phrased, incorporated an inaccurate representation of the law, for the proposed wording implied that a person found guilty of second degree murder would be incarcerated for at least twenty years. An instruction informing the jury of sentencing possibilities would have correctly stated that the minimum range of actual confinement, in terms of parole eligibility, is from one day to one-third of twenty years.

In point of fact, the trial judge did charge the jury on the elements of second degree murder, as a lesser included offense of first degree murder, but the underlying issue raised by appellants is whether they were entitled to any sort of instruction specifying the penalty for that offense. We hold that they were not. The judge ruled that such an explanation is required by law only for the charge of first degree murder, but that in every other instance sentencing in this circuit is solely the province of the court, not of the jury. We agree with the trial judge that that is an accurate view.

Timm requested an instruction relating to an incident which occurred on cross-examination of one of his expert witnesses. During questioning by the prosecutor, Dr. Maguigad testified that he had been retained by Timm's father; when asked whether his fee had been paid prior to his appearance in court, he answered in the negative. Thereupon Timm's counsel objected at the bench, urging that such a line of inquiry was irrelevant. The court agreed, but responded that it would "just . . . let the whole thing lie," and the matter was pursued no further at that time. At the close of the case, however, Timm asked that the jury be instructed "on the fact that expert witnesses are entitled to be paid for their services." In denying this request, the trial judge concluded that it was "not necessary at this point."

We sympathize with Timm's apprehension that jurors might have concluded that, since he had not been paid, Dr. Maguigad's compensation would depend on the success of his testimony. And we think that the better practice would have been to give a cautionary instruction immediately following such an improper question. As to Timm's request for the instruction just prior to the jury's retirement for deliberations, the judge estimated that the impact of the question had been dissipated by the lapse of time between its asking and the charging of the jury; in short, that remark was of a minor nature in the context of a three-week trial, and perhaps more harm would have been done by dredging the subject up once again. On this point we defer to the trial judge's evaluation, based as it was upon first-hand observation of the entire range of events which transpired during the trial.

The final contention goes to the substance of the instruction on burden of proof of insanity. The question is whether the court properly charged that appellants had to establish their insanity defenses by a preponderance of the evidence for both the federal and the District of Columbia code offenses on trial. The District of Columbia Court Reform and Criminal Procedure Act of 1970 modified the existing practice by enactment of a new provision, the present Section 24-301(j) of the District of Columbia Code to impose the burden of proof of insanity upon the defendant. In their briefs appellants argued that having to maintain that burden is a denial of due process of law; additionally, they argued, the instruction erroneously required them to prove the productivity element of their insanity defenses.

In this court's decision in United States v. Greene, announced subsequent to the filing of appellants' briefs, both of these arguments were squarely rejected as to trials of nonfederal offenses in the District Court. The Greene opinion holds that as to such trials Section 207(6) involves no due process or equal protection violation, and permits no distinction between productivity and other elements of an insanity defense. Appellants continue to urge, however, that the requirement that an accused in the District of Columbia prove insanity as a defense to a federal criminal charge denies the equal protection of the laws since in every other federal district that burden rests with the Government. This question was expressly left open in Greene and appellants ground their position on United States v. Thompson, an earlier decision of the court. Appellants read Thompson as a barrier to adoption of a common standard of proof for District of Columbia and federal charges if that standard differs adversely from one in vogue for defendants in criminal cases in federal jurisdictions elsewhere in the Nation. With equal vigor, the Government defends the application of Section 207(6) to trials of federal as well as nonfederal offenses committed in the District of Columbia.

We deem it unnecessary, however, in the circumstances presented, to resolve on the merits that issue in the instant case. We note, on the one hand, a serious and complex constitutional question with no controlling precedent directly in point, and the toll its decision will take on the court's resources at this time. On the other hand, we note the interrelationship of numerous convictions of appellants stemming from facets of two separate but internally integrated criminal episodes, and the concurrency of the sentences, in all instances save one, which the trial judge imposed on those convictions.

To recapitulate, Timm incurred nine nonfederal convictions, and Caldwell eight, on which each was sentenced to incarceration for terms extending upwardly to life imprisonment. Eliminating therefrom, as we must, three duplicitous convictions of each applicant for lesser-included offenses, both appellants are left with multiple nonfederal convictions and the same range of sentences, all of which we are prepared to affirm. As it is, with respect to the federal convictions, one of the three for bank robbery — by each appellant — must be vacated as invalid, and the two remaining and two additional federal convictions bear sentences shorter than, and concurrent in operation with, the life terms assessed on the nonfederal felony-murder conviction. The net result is that the sentences on the federal convictions contribute nothing whatsoever to the penalties which appellants owe to society in consequence of the nonfederal offenses.

Four years ago, we faced a cognate situation in United States v. Hooper, and there we laid down a doctrine which has done useful service to this court and, in the longer run, to the community. There an appeal brought on for review two convictions, one federal and the other nonfederal, arising out of a single robbery, and tendered for decision the difficult question whether both convictions and the concurrent sentences on them could stand. Since we found no error warranting reversal of the nonfederal conviction, we saw "no reason to devote our time and energies to research, and opinion-writing, incident to appropriate determination of an issue not governed by controlling precedent when no present public interest or need is furthered thereby." We declared that "[i]t better serves the general interest of the administration of justice if the court limits its resources to the determination of those questions and cases that must be decided, especially in view of the ever-mounting docket that besets this and other appellate courts." Adverting to our "broad discretion" statutorily conferred "to direct the entry of such judgment or order as will further the interest of justice," and observing that vacation of the federal conviction and sentence "does not impair any need of the government, avoids the possibility of adverse collateral consequences to defendant, and furthers the general interest of the administration of justice," we felt "it in the overall interest of justice that, without determination of the merits," we vacate the conviction on the federal charge.

We think these considerations chart the same course here. Accordingly, we vacate the federal convictions and the sentences levied upon appellants. We instruct, as we did in Hooper, that "[i]f it later develops that the interest of justice so requires, the sentence[s] can be reimposed on a concurrent basis," and that "[t]he conviction[s] could then be subject to appellate review." We vacate also the nonfederal convictions and sentences for lesser offenses already included in other convictions and sentences. We reiterate that none of these actions will affect appellants' maximum terms of imprisonment one whit. In all other respects, we affirm the judgments subjected to these appeals.

So ordered.

SPOTTSWOOD W. ROBINSON, III, Circuit Judge:

Supplemental Opinion on Appellants' Petitions for Rehearing (D.C.Criminal Nos. 1420-71 1421-71).

SPOTTSWOOD W. ROBINSON, III, Circuit Judge:

Pending the Supreme Court's decision in Mullaney v. Wilbur, we deferred action on appellants' petitions urging rehearing and reversal of our holding that the District Court was constitutionally authorized to instruct the jury, in full conformity with statute, that appellants bore the burden of proving by a preponderance of the evidence their insanity defenses to the nonfederal charges on trial. In so concluding, we relied upon this court's decision in United States v. Greene sustaining the operation of the statute in trials of District of Columbia Code offenses against claims of due process and equal protection violations. Mullaney holds that Maine's requirement that one accused of murder demonstrate provocation reducing the offense to manslaughter disobeys the Fourteenth Amendment's due process command, delineated in the Court's earlier Winship decision, that the state prove beyond a reasonable doubt every factual element of a crime underlying conviction. Largely on that ground, appellants now renew their due process attack.

Mullaney's significance to the instant case can be appraised only in the context of our application of Greene as the controlling precedent. Greene rested on Leland v. Oregon, wherein the Supreme Court upheld the state's allocation to the accused of the burden of proving insanity as an imposition not treading upon "generally accepted concepts of basic standards of justice." That conclusion was reached long after formulation of the Davis rule — an exercise of the Court's supervisory authority — that the Government has that burden in federal prosecutions. And despite the Court's broader constitutional rulings in Winship five years ago and in Mullaney within recent months Leland has not been expressly overruled.

Appellants assert, however, that Winship and Mullaney have sub silentio set Leland for naught, and that in the case at bar we should so hold. In our view, we lack that prerogative. In Greene, the panel rejected a similar invitation, this court denied rehearing en banc, and the Supreme Court declined further review. As but another panel of the court, we are not at liberty to disregard these events. Moreover, while appellants' argument would have merit if its premise were acceptable, any undertaking to predict Leland's fate at the Supreme Court's hand would likely amount to no more than a bold but unfruitful venture in speculation. Only two weeks after granting a writ of certiorari to review Mullaney, the Court denied a writ in Greene, and later refused to rehear the denial. In both Winship and Mullaney a majority of the Court made only passing reference to Leland. The only positive indication emerging is the position of the two members concurring in Mullaney that Leland retains its vitality.

In this milieu, it is not for us to declare the challenged statute unconstitutional on the theory that Leland is dead. Our duty is to abide Leland as long as the Supreme Court has not made its demise plain, and that, to say the least, has not been done. Appellants, of course, are free to ask the Court for a reexamination of Leland and a determination as to its viability.

Petitions denied.

SPOTTSWOOD W. ROBINSON, III, Circuit Judge:

ORDER

Appellants' suggestions for rehearing en banc and supplemental memorandum in support thereof having been transmitted to the full Court and there not being a majority of the Judges in regular active service in favor of having this case reheard en banc, it is

Ordered by the Court en banc that the aforesaid suggestions for rehearing en banc are hereby denied.