Opinion for the court filed by McGOWAN, Circuit Judge.
Opinion filed by MacKINNON, Circuit Judge, concurring in part and dissenting in part.
McGOWAN, Circuit Judge:
These consolidated appeals present troublesome questions about the division of criminal jurisdiction between the federal and local courts in the District of Columbia. When alleged U.S.Code and D.C.Code violations are properly joined in a single indictment, the District of Columbia Court Reform and Criminal Procedure Act of 1970 permits all crimes charged to be tried together in the United States District Court. In this case, however, we decide that the District Court lacked jurisdiction over the D.C. robbery offense charged in appellants’ indictment. We hold first that the robbery count was improperly joined with the remaining offenses of which appellants were accused. Alternatively, we hold that, even if the original joinder of the robbery count
[791]*791was proper, the District Court divested itself of jurisdiction over that count when it granted appellants’ pretrial motion to sever the robbery charge in order to avoid the possibly prejudicial atmosphere of a single trial.
Accordingly, we reverse appellants’ robbery conviction. Finding no infirmity with the other convictions challenged here by appellant Jackson, we affirm that portion of the District Court’s judgment which reflects the jury’s verdict in appellants’ first trial.
I
The events giving rise to these appeals occurred near a tavern in southwest Washington in the early morning hours of April 26, 1975. At about 1:45 A.M., two women, Dari Tritt and Kathy Kirch, left the Pier Nine restaurant and bar. Almost immediately, they were accosted at gunpoint by a man who had just emerged from a late-model gold Chevrolet parked near the intersection of Half and V Streets. This individual, later identified as appellant Jackson, instructed the women to walk toward the Anacostia River. When Ms. Kirch attempted to “talk [her] way out of it,” Jackson hit her across the face with sufficient force to knock her to the ground and cause bleeding. The women proceeded to walk in the direction indicated by their assailant. Arriving at the water’s edge, they were ordered to disrobe. When they did not comply quickly enough, their attacker ripped off Ms. Kirch’s blouse. After Ms. Kirch had also removed her bra, Jackson’s attention was distracted by a noise, and Ms. Kirch was able to wrest the sawed-off rifle from his grasp. Jackson fled, and the two women returned to the Pier Nine bar and notified police.
A short while later, Marliese Nakamura, her mother, and a male friend left the Pier Nine, and walked to their nearby car. As they were about to enter, another car, a gold Chevrolet, approached slowly. A man in the passenger seat of the Chevrolet reached out the car window and grabbed Ms. Nakamura and her purse. The young woman was dragged approximately ten feet before she let go of her handbag. The bag contained a topaz necklace, a checkbook, various pieces of identification, a small evening purse belonging to Ms. Nakamura’s mother, and a wallet belonging to Lawrence Gorman, the friend. Among the contents of the elder Ms. Nakamura’s purse were three of her lipstick cases and a prescription bottle belonging to her daughter. Mr. Gorman’s wallet contained approximately $100 in cash.
After the purse snatching, Mr. Gorman and the Nakamuras chased the gold Chevrolet in their own car. Although the fleeing car eventually managed to elude its pursuers, Mr. Gorman and the Nakamuras were able to obtain the Chevrolet’s license plate number, and to observe that its occupants were two black men, one of whom, the driver, was wearing a green print shirt. When the chase proved unsuccessful, the trio returned to the Pier Nine bar and called the police.
Upon receiving the gold Chevrolet’s license number from Mr. Gorman, the police checked the registration and found that the car’s owner listed a home address in the 700 block of 12th Street, Southeast. Approaching this location in his squad car, Metropolitan Police Lieutenant Spurlock saw a gold Chevrolet bearing a license number which matched that obtained from Mr. Gorman and Ms. Nakamura. At 12th and I Streets, Southeast, Lt. Spurlock stopped the car, and arrested its occupants, appellants Jackson and Johnson. Appellant Johnson was wearing a shirt like that described by Mr. Gorman and the Nakamuras. The Chevrolet was also taken into custody. A subsequent search of the car revealed a sack of rifle ammunition of the same caliber as the weapon which Ms. Kirch had taken from her assailant. Also discovered in the Chevrolet were Ms. Nakamura’s handbag, her prescription bottle, and her mother’s lipstick. None of the remaining contents of the purse were found.
Informed of appellants’ arrest, police at the Pier Nine bar brought Dari Tritt and Gisela Nakamura, Marliese’s mother, to the [792]*792southeast Washington location where appellants had been apprehended. Ms. Tritt was unable to identify either appellant as the man who forced her and Ms. Kirch to accompany him to the river bank. However, the elder Ms. Nakamura, relying primarily on the color and pattern of appellant Johnson’s shirt, did identify Johnson as the driver of the gold Chevrolet. Appellants were then taken to George Washington University Hospital, where Ms. Kirch had gone for X-rays. Ms. Kirch did not recognize appellant Johnson, but she did identify appellant Jackson as her attacker.
In a nine-count indictment filed on May 22,1975, appellants were each charged with possession of an unregistered firearm (26 U.S.C. § 5861(d) (1970)); possession of a firearm not identified by serial number (26 U.S.C. § 5861(i)); robbery (22 D.C.Code § 2901 (1973)); assault with intent to commit rape while armed (two counts; 22 D.C. Code §§ 501, 3202); assault with intent to commit rape (two counts; 22 D.C.Code § 501): and assault with a dangerous weapon (two counts; 22 D.C.Code § 502).
With the exception of the robbery count, all charges against appellants stemmed from the incident involving Ms. Tritt and Ms. Kirch. As a consequence, trial counsel for appellants moved to sever the robbery count, alleging both improper joinder under Fed.R.Crim.P. 8, and the likelihood of prejudice within the meaning of Fed.R.Crim.P. 14. The motion was granted by the District Court,1 and appellants were tried on the remaining eight counts of the indictment. At the conclusion of this trial, on November 20, 1975, appellant Johnson was acquitted; and appellant Jackson was convicted of possession of an unregistered firearm and two counts of assault with intent to commit rape while armed. Approximately six months later, appellants were tried in District Court on the robbery charge which had been severed. Both were convicted. For his offenses, appellant Jackson was sentenced to concurrent terms under the Youth Corrections Act, 18 U.S.C. § 5010(b) (1970). On the basis of his robbery conviction, appellant Johnson was sentenced to a prison term of twenty months to five years.
II
Of the numerous assignments of error pressed upon us, only those concerning the District Court’s jurisdiction over the robbery count merit extended discussion. As a preliminary matter, we briefly dispose of two other arguments advanced by appellants. We believe first of all that the police unquestionably had probable cause to arrest appellants when they did. A gold Chevrolet was mentioned prominently in reports of two crimes occurring in the vicinity of the Pier Nine bar. Appellants were observed driving such a vehicle near that general location shortly after the crimes were committed. Moreover, the license number of appellants’ car matched exactly the number of the gold Chevrolet obtained from the victims of one of the crimes. Taken together, these circumstances surely constituted probable cause for arrest.
Likewise, we are not persuaded by appellant Jackson’s contention that the evidence was insufficient to support his conviction of assault with intent to commit rape while armed. The requisite intent need not be proved by direct evidence, but may be inferred from the totality of the circumstances presented to the jury. Here, the evidence adduced at trial tended to show that appellant Jackson led Ms. Tritt and Ms. Kirch at gunpoint to a secluded spot on the bank of the Anacostia River, and then ordered them to remove their clothing. In addition, testimony indicated that Jackson impatiently ripped off Ms. Kirch’s blouse when she failed to follow instructions swiftly enough. From these facts, we believe [793]*793the jury could permissibly infer beyond a reasonable doubt that Jackson possessed the intent necessary to sustain a conviction for the offense charged. While no purpose would be served by detailed commentary on the cases cited by appellant in support of a contrary position, we have examined those precedents and find them clearly distinguishable from the present case.
Ill
We turn now to the only substantial issue presented by these appeals, namely, the propriety of appellants’ robbery conviction. At the outset, we look to the language of the relevant jurisdictional statute, 11 D.C.Code § 502(3) (1970):
[T]he United States District Court for the District of Columbia has jurisdiction of . . [a]ny offense under any law applicable exclusively to the District of Columbia which offense is joined in the same information or indictment with any Federal offense.
The word “joined” in this provision must be construed to mean “properly joined under Fed.R.Crim.P. 8.” If it were not so construed, federal jurisdiction over purely D.C. offenses could be invoked any time a defendant faced prosecution for both federal and D.C. crimes, regardless of how unconnected or dissimilar those crimes might be. If “joined” did not mean “properly joined,” jurisdiction over D.C. offenses could be conferred upon the District Court by the simple expedient of adding at least one federal count to any indictment. Plainly, this would be an unacceptable situation, since a major purpose of the District of Columbia Court Reform and Criminal Procedure Act of 1970 was to shift general jurisdiction over D.C.Code offenses from the United States District Court to the Superior Court of the District of Columbia.
In order to determine whether joinder of the robbery count with the rest of the indictment was proper in this case, we look to Fed.R.Crim.P. 8.2 Where multiple defendants are involved, Fed.R.Crim.P. 8(b) governs both joinder of offenses and joinder of defendants. This is certainly not apparent from the language of the Rule itself. Rule 8(a) is entitled “Joinder of Offenses,” and Rule 8(b) is labelled “Joinder of Defendants.” Nevertheless, the weight of authority in this circuit and elsewhere regards Rule 8(b) as providing the sole standard for determining the permissibility of joinder of offenses where more than one defendant is involved. See, e. g., Cupo v. United States, 123 U.S.App.D.C. 324, 359 F.2d 990 (1966) (Edgerton, J.), cert. denied, 385 U.S. 1013, 87 S.Ct. 723, 17 L.Ed.2d 549 (1967); United States v. Granello, 365 F.2d 990 (2d Cir. 1966), cert. denied, 386 U.S. 1019, 87 S.Ct. 1367, 18 L.Ed.2d 458 (1967), and King v. United States, 355 F.2d 700 (1st Cir. 1966). But see Scheve v. United States, 87 U.S.App.D.C., 289, 184 F.2d 695 (1950) (Edgerton, J.).
Sometimes cited in support of the majority reading of Rule 8 is the Advisory Committee Note to the Federal Rules of Criminal Procedure (Second Preliminary Draft 1944).3 The crucial sentence states, “Subdivisions (a) and (b) are intended to keep distinct the joinder of charges and of defendants, a distinction which frequently is not observed.” At 38. Arguably, at least, this sentence does not dictate the interpre[794]*794tation which the courts have given to Rule 8(b). Absent the bulk of precedent, the language and history of Rule 8 would leave the matter unsettled. Noting the Rule’s drafting deficiencies, one leading commentator has observed that “[n]one of the Federal Rules has given rise to so much misunderstanding.” 8 Moore’s Federal Practice 18.02[1], at 8-2 (2d ed. 1976). Professor Wright’s summary is helpful:
It is firmly established in the case law that the propriety of joinder in cases where there are multiple defendants must be tested by Rule 8(b) alone and that Rule 8(a) has no application. It may well be doubted if this was the intention of the draftsmen. It is quite possible that they contemplated that joinder of defendants would be proper if Rule 8(b) were satisfied and that Rule 8(a) would then be looked to in determining what offenses might be joined against the defendants so named. This would be consistent with the pattern of the Civil Rule that the draftsmen seem generally to have taken as their model.
1 C. Wright, Federal Practice and Procedure, § 144, at 318-19 (1969) (footnotes omitted.)
Assuming, then, that Rule 8(b) governs, the robbery count could be joined to the rest of the indictment only if all the offenses charged were part of “the same series of acts or transactions.” According to the evidence presented at trial, the purse snatching which formed the basis of the robbery charge occurred shortly after the assault and in approximately the same location as the earlier crime. Since the two offenses were not otherwise related, the question becomes whether mere temporal and spatial proximity can justify characterization of the assault and the robbery as different parts of “the same series of acts or transactions”.4
In King, supra, Chief Judge Aldrich espoused adoption of a pragmatic approach in determining when multiple offenses may be subsumed in a single “series of acts or transactions.”
[Joinder of offenses under] Rule 8(b) is not limited to situations in which proof of the other criminal transaction would be admissible in a separate trial. It goes beyond, to others, the excuse being the benefit to the courts. . . . [T]his possibility of benefit should explicitly appear from the indictment or from other representations by the government before trial. Classic examples of such a benefit are when there is an overlapping of issues, as, for example, when some [795]*795defendants are charged with transporting stolen goods in interstate commerce and others are charged with receiving the goods, so stolen and transported, or when defendants are charged with conspiracy to conceal a crime that part of their number are charged with committing. Where, however, there are no presumptive benefits from joint proof of facts relevant to all the acts or transactions, there is no “series,” Rule 8(b) comes to an end, and joinder is impermissible.
355 F.2d at 704 (footnote and citations omitted).
In its brief on appeal in this case, the Government devotes scant attention to the improper joinder point raised by appellants. The relevant section of the brief, Part IV, occupies little more than one page, and consists solely of a capsule summary of the facts, a reproduction of Rule 8(b), and a' bare assertion that the “circumstances provide more than adequate grounds for joinder.” Brief for Appellee at 35.
In its opposition to defendants’ motion for severance in the trial court, the Government did discuss the matter in greater detail. Relying on Drew v. United States, 118 U.S.App.D.C. 11, 331 F.2d 85 (1964), the Government argued first that the robbery and assault herein “arose out of a continuing transaction or the same set of events,” and that therefore “the evidence of each of the crimes on trial would be admissible in a separate trial for the other.” Under these circumstances, the Government continued, joinder should clearly be permitted since “the prejudice that might result from the jury’s hearing the evidence of the other crime in a joint trial would be no different from that possible in separate trials.” 331 F.2d at 90. Secondly, the Government maintained that “the crimes charged are so interrelated that it would be impossible to adequately prove one without incidentally proving the other.” Opposition to Defendants’ Motion for Severance at 4.
Both prongs of the Government’s position were expounded in thoroughly eonclusory terms.5 At no point did the Government indicate what facts, apart from defendants’ presence at the approximate time and place of the two crimes, would be amenable to joint proof. Under the First Circuit’s test in King, the very limited benefits to be derived in this case from the opportunity to present joint proof might well be thought to be insufficient to counterbalance the risk of prejudice created by joinder of the assault and the robbery.
On the other hand, the Commentary to the ABA Standards on Joinder and Severance reports that “[i]t is common to permit joinder of offenses committed at approximately the same time and place.” Approved Draft of ABA Project on Minimum Standards for Criminal Justice at 12. Unfortunately for our purposes, this statement cannot be taken at face value. As examples of the general rule, the ABA Commentary lists “the killing of several people with successive shots from a gun or the successive burning of several structures,” citing Scott v. State, 211 Wis. 548, 248 N.W. 473 (1933).6 These illustrations do not correspond neatly to the facts presented in the current case. Here, we are confronted with dissimilar and apparently unconnected crimes, and we are provided with little or no indication of how or why defendants moved from one to the other. We know only that the crimes occurred at about the same time and about the same place.
[796]*796A possible additional problem with the ABA Commentary is that it focuses on the language of Rule 8(a), rather than 8(b). Where only a single defendant is involved, Rule 8(a) would allow joinder of offenses which are
of the same or similar character or are based on the same act or transaction or on two or more acts or transactions connected together or constituting parts of a common scheme or plan.
The major distinction between subdivisions (a) and (b) lies in their treatment of offenses “of the same or similar character.” As long as only one defendant is concerned, Rule 8(a) permits joinder of such offenses, even if they are entirely unrelated to each other. On the other hand, in the multiple defendant context, Rule 8(b) forbids joinder, even of identical crimes, unless those crimes are part of “the same series of acts or transactions.” As this court has explained,
When similar but unrelated offenses are jointly charged to a single defendant, some prejudice almost necessarily results, and the same is true when several defendants are jointly charged with a single offense or related offenses. Rule 8(a) permits the first sort of prejudice and Rule 8(b) the second. But the Rules do not permit cumulation of prejudice by charging several defendants with similar but unrelated offenses.
Cupo, supra at 993 (footnote omitted). Indeed, courts differentiating between subdivisions (a) and (b) almost invariably do so in response to prosecutorial attempts to indict two or more defendants together for similar, but unrelated, crimes. See, e. g., United States v. Whitehead, 539 F.2d 1023 (4th Cir. 1976); United States v. Marionneaux, 514 F.2d 1244 (5th Cir. 1975), and Granello, supra. See also 1 C. Wright, Federal Practice and Procedure § 144, at 319 (1969) (approving the prevailing judicial construction of Rule 8).
Given the nature of the primary distinction between subdivisions (a) and (b) discussed in the preceding paragraph, speculation has arisen that Rule 8(b)’s phrase, “the same series of acts or transactions,” may be essentially coterminous with the wording employed in the last portion of Rule 8(a), “two or more acts or transactions connected together or constituting parts of a common scheme or plan.” Professor Wright has stated the argument cogently:
Rule 8(b) does not define what is meant by “the same series of acts or transactions.” It is a less meaningful phrase than is used in Rule 8(a) where the phrase is “two or more acts or transactions connected together or constituting parts of a common scheme or plan.” Resort to the dictionary would permit any set of acts to be regarded as a “series,” but if this were done, the purported limitation imposed by Rule 8(b) would be meaningless. One possibility would be to read “series” in Rule 8(b) as if it meant the kind of relation more specifically described in Rule 8(a). Thus if acts were part of a common scheme or plan, or connected together, they could be regarded as a series. Such a reading would not be inconsistent with the results reached in the cases.7
1 C. Wright, Federal Practice and Procedure, § 144, at 322 (1969). See also 8 Moore’s Federal Practice 1806[1], at 8-24; Id. H 8.06[2], at 8-37 (2d ed. 1976).
Unhappily, resort to the language of Rule 8(a), even if compatible with precedent and the draftsmen’s intent, brings us no closer to resolution of the controversy before us. For the fundamental question remains: Are crimes committed by the same persons around the same place and around the same time automatically sufficiently “connected together” to be joined in one indictment?
The general policy underlying Rule 8 might indicate an affirmative answer. Courts have frequently said that the Rule should be interpreted broadly in favor of [797]*797initial joinder. See, e. g., Haggard v. United States, 369 F.2d 968 (8th Cir. 1966), cert. denied, 386 U.S. 1023, 87 S.Ct. 1379, 18 L.Ed.2d 461 (1967); and United States v. Friedman, 445 F.2d 1076 (9th Cir.), cert. denied, 404 U.S. 958, 92 S.Ct. 326, 30 L.Ed.2d 275 (1971). The rationale for this canon of construction is twofold. First, Rule 8 is permissive, not mandatory. Initial joinder may be legitimate under the Rule, but the trial court may nevertheless grant a severance of some counts at a later time in order to avoid prejudice to the defendant (or the Government). See Fed.R. Crim.P. 14.8 Since joinder of offenses in an indictment does not represent an irreversible commitment to joint trial of those offenses, conventional wisdom has favored a liberal reading of Rule 8.9 Moreover, defendants may actually prefer joinder in some instances; in order to avoid the inconvenience and expense of successive trials and to minimize the potential for imposition of consecutive sentences, they may prefer, where the possibility of prejudice seems slight, to be tried simultaneously on all charges pending against them. See ABA Commentary, supra, at 11.
In sum, the joinder of offenses in this case presents an exceedingly close question under Rule 8. The Government has neither demonstrated nor alleged any logical link between the assault and the robbery of which appellants were accused. While joinder in a single indictment may well have been appropriate under the ordinary judicial construction of the governing Rule, one further point remains to be made regarding the peculiar role of the joinder issue in this case. Typically, when Rule 8 is invoked, the court’s only problem is whether or not to sever.10 In practical terms, the court must decide whether to conduct one trial or two.
Here, however, resolution of the joinder issue has jurisdictional significance. If the robbery count was not properly joined to the rest of the indictment, the District Court was not free to try it separately. Rather, the District Court would have lacked jurisdiction to try it at all. When Rule 8 is thus applied for jurisdictional purposes, the considerations counselling liberal construction of the Rule no longer seem compelling. Since Congress has determined that D.C. offenses should generally be tried in the D.C. courts, the joinder provisions of Rule 8 should not be strained to uphold federal jurisdiction over local crimes. We hold that, on the facts presented here, joinder of the robbery count with the other charges against appellants was improper, and therefore conferred upon the District Court no jurisdiction over the alleged D.C. Code offense of robbery.
[798]*798IV
Alternatively, we assume that initial joinder of the robbery count was proper under Rule 8(b), and then address the District Court’s retention of jurisdiction over the robbery count after severance pursuant to Rule 14. In this connection, the first point to be made is that United States v. Shepard, 169 U.S.App.D.C 353, 515 F.2d 1324 (1975), is not controlling. In Shepard, defendant was tried simultaneously for federal and D.C. offenses which derived from the same factual circumstances. At the close of evidence, but before submitting the case to the jury, the Government elected to dismiss the federal charge because of “discrepancies in the indictment.” Thereafter, the District Court allowed the remaining counts of the indictment, alleging only D.C. crimes, to go to the jury. Defendant was convicted of armed robbery, and appealed, claiming that dismissal of the federal count deprived the District Court of jurisdiction over the joined D.C. offenses. This court affirmed, holding that
where federal and local offenses have been properly joined in one indictment and jeopardy has attached, the District Court may proceed to a determination of the local offenses regardless of any intervening disposition of the federal counts.
515 F.2d at 1331 (emphasis added).
In its memorandum opinion retaining jurisdiction over the robbery count in the appeals now before us, the District Court stated, “Since jeopardy has not attached as to count nine, the explicit holding of Shepard [sic] is not dispositive.” Counsel for appellants, both in his memorandum of law before the District Court and in his brief on appeal, conceded that, after severance of the robbery count and after completion of trial on the remainder of the indictment, no jeopardy had yet attached with respect to the robbery charge in the District Court. Memorandum of Law at 2, December 12, 1975; Brief for Appellants at 34. This plainly could not have been said concerning the D.C. crimes of which defendant was accused in Shepard. Those crimes had been completely tried to a jury before any question of the District Court’s jurisdiction arose. And, as this court declared in Shepard, “Once the District Court swears in the jury, jeopardy attaches as to all counts in the indictment, both federal and local.” This court’s sustenance of District Court jurisdiction in Shepard, then, does not dictate a similar result in connection with the robbery offense at issue here.
In Shepard, the Government conceded that “the dismissal of all federal charges prior to trial would require the dismissal of the remainder of the indictment as well.” 515 F.2d at 1329. See also Brief for Government in Shepard at 10. Appellants rely on this concession, and seek to analogize the situation after severance here to that in which all federal counts had been dismissed before trial. The Government now characterizes its own concession in Shepard as dictum of this court, “derived . from an incomplete research of the doctrine of pendent jurisdiction.” Government’s Memorandum in Support of the Court’s Jurisdiction to Try the Remaining Robbery Count at 3. Thus the Government apparently wishes to repudiate its concession in Shepard, and to adopt instead the position that neither dismissal of federal charges before trial nor severance of such charges will negate federal District Court jurisdiction over properly joined D.C. offenses.
In support of its revised stance, the Government has marshalled two arguments. The first of these stresses the language of the relevant jurisdictional statute, 11 D.C.Code § 502(3) (1970). That provision, reproduced in the text at 6 supra, grants the District Court jurisdiction over any D.C. offense “joined in the same information or indictment with any federal offense.” Commenting on § 502(3), the Shepard court said:
This is unequivocal language. The statute makes no reference to any other disposition of the joined counts charging D.C. offenses in the event all counts charging federal offenses are dismissed [or, we may now add, severed].
[799]*799515 F.2d at 1329. Indeed, the language is unequivocal. But that alone does not imply a Congressional intent that the federal courts should retain jurisdiction over purely D.C. offenses irrespective of the disposition of the federal charges whose joinder originally conferred jurisdiction over the local crimes. On the contrary, the lack of qualification in § 502(3) suggests that Congress, in framing the District of Columbia Court Reform and Criminal Procedure Act, simply did not consciously confront the sort of problem presented here. A search of the House, Senate, and Conference Committee Reports accompanying the Act has yielded nothing more than the lone comment already uncovered by the Shepard court:
Some overlapping of jurisdiction will inevitably remain, that being only a minor percentage of cases primarily arising when the same person is accused of infractions which are both Federal and purely local violations (and in those cases the United States Attorney will handle all charges with minimal procedural difficulties).
H.R.Rep.No.91-907, 91st Cong., 2d Sess. 33 (1970). This controversy, of course, belies the optimism of the House Committee’s parenthetical remark. In short, the legislative history is unhelpful, and, if anything, cuts against the Government’s ascription of substantial significance to the unqualified language of § 502(3).
To bolster its case in favor of the District Court’s retention of jurisdiction over the severed robbery count herein, the Government has turned to the civil law doctrine of pendent jurisdiction. In particular, the Government seeks to draw support from Rosado v. Wyman, 397 U.S. 397, 90 S.Ct. 1207, 25 L.Ed.2d 442 (1970). There, plaintiffs attacked the New York Social Services Law as violative of the Equal Protection Clause of the Fourteenth Amendment. Plaintiffs also asserted that the same state statute was incompatible with the federal Social Security Act. The Supreme Court held that, despite the undisputed mootness of plaintiffs’ constitutional claim, the District Court nevertheless properly exercised jurisdiction over the pendent statutory claim. 397 U.S. at 402-05, 90 S.Ct. 1207. After a brief review of the Rosado decision, the Government concludes, “If 11 D.C.Code § 502(3) does not compel the trial court to retain jurisdiction [over the robbery count] in these circumstances, the doctrine of pendent jurisdiction clearly allows it.” Brief for Appellee at 39.
This extrapolation from Rosado is questionable for at least two reasons. First, as a general matter, wholesale importation of civil law concepts into the criminal sphere is a practice fraught with danger. While recognizing that “the doctrine of pendent jurisdiction has only been applied in civil cases and thus is not directly relevant in the criminal context presently before us,” the Shepard panel did indicate that the pendent jurisdiction analogy might prove useful in the interpretation of § 502(3). 515 F.2d at 1330-31. However, this analogy must be applied with great care. As Professor Moore has commented in connection with Rule 8, “The civil model ... is often inappropriate in criminal procedure, and no subject illustrates this fact better than joinder.” 8 Moore’s Federal Practice 118.02[1], at 8-3 (2d ed. 1976). Efficiency — “the conservation of judicial energy and the avoidance of multiplicity of litigation” — may be pursued with single-minded devotion in the rules and doctrines of civil procedure, but, on the criminal side, solicitude for efficient judicial administration must sometimes give way to the need to protect the rights of defendants.
Secondly, and completely apart from broad doubts concerning the transferability of civil law concepts to the criminal arena, the facts in Rosado made the notion of pendent jurisdiction much more appealing there than it is here. Justice Harlan’s opinion for the Court called attention to the two primary factors affecting the discretionary exercise of pendent jurisdiction: “the extent of the investment of judicial energy and the character of the [pendent] claim.” 397 U.S. at 403, 90 S.Ct. at 1213. In Rosa-do,
[n]ot only had there been hearings and argument prior to dismissal of the consti[800]*800tutional claim, but the statutory question is so essentially one “of federal policy that the argument for exercise of pendent jurisdiction is particularly strong.”
Id. at 403-04, 90 S.Ct. at 1213 (footnote omitted). Here, at the time of severance, virtually no judicial energy had been directed toward disposition of the robbery count; moreover, defendants’ ultimate guilt or innocence of the robbery charge implicated federal law not at all. Thus, even accepting the basic legitimacy of the pendent jurisdiction analogy, Rosado offers little or no encouragement for the Government’s attempted reliance on the concept in this case.
To recapitulate, neither Shepard, nor the language of § 502(3), nor the doctrine of pendent jurisdiction, provides convincing support for the District Court’s retention of jurisdiction over the robbery count herein. Likewise unpersuasive in light of the strong Congressional policy favoring trial of D.C. offenses in the D.C. courts are the various spectres which, the Government and the District Court warn, will haunt the judicial process if severance triggers a lapse of federal jurisdiction here: inevitable delay arising from the need to reindict, possible relitigation of preliminary issues already once resolved by the federal courts, and inhibition of the trial court’s decision on whether to grant severance in order to avoid prejudice.
Finally, and perhaps most importantly, the District Court should not retain jurisdiction after severance here because of the close relationship between Rules 8 and 14. As explained earlier (see notes 8 and 9 and accompanying text supra), liberal joinder is generally permitted under Rule 8 because trial courts know they can take refuge in Rule 14 upon a showing that a joint trial may prejudice defendant(s). Since severance for misjoinder under Rule 8 unquestionably leaves the District Court without jurisdiction over the severed counts (where those counts allege purely local offenses), and since, under prevailing practice, severance pursuant to Rule 14 is frequently a substitute for severance under Rule 8, the District Court’s reliance here on Rule 14 rather than Rule 8 should not have the far-reaching jurisdictional consequences which the Government would attach to it.
The responsibilities of the District Court with respect to matters of federal concern are great and growing. A central purpose and policy of D.C. court reorganization was to assure that the prompt and effective discharge of those responsibilities would not be impeded by the necessity of trying local criminal offenses, for which a forum was provided in an enlarged and strengthened local court system. The authority conferred by 11 D.C.Code § 502(3) should not be extended by either prosecutor or judge beyond its precise limits. Upon either of the two grounds articulated in this opinion, we find the District Court to have been lacking in jurisdiction with respect to the charge of robbery.
Appellants’ robbery conviction is therefore reversed. The remaining convictions of appellant Jackson are affirmed.