Opinion for the Court PER CURIAM.
Separate Opinion of Circuit Judge MacKINNON in which Circuit Judge ROBB concurs. Opinion Concurring in part and Dissenting in part filed by Circuit Judge, SPOTTSWOOD W. ROBINSON, III. Concurring and Dissenting Opinion in which Chief Judge SKELLY WRIGHT joins filed by Senior Circuit Judge BAZELON. PER CURIAM:In this opinion the court considers the application of the rulings in its recent en banc opinion in Decoster1 to a claim of ineffective assistance of counsel by reason of failure to provide appropriate presentation of a defense of insanity.
1. Factual Background
In November 1970 Michael Wood was committed to St. Elizabeths Hospital, having been acquitted by Reason of insanity in the trial of two criminal charges. On the evening of February 28, 1972, Mr. Wood and three other patients at St. Elizabeths forced two nurses’ assistants into a utility room, threatening one with a knife and taking from him his hospital keys and $33 in cash. The assistants were handcuffed together and locked in the utility room, and the four patients fled the hospital. In April 1972 Mr. Wood was captured by the F.B.I. and returned to St. Elizabeths.
As a result of his elopement, Mr. Wood was charged with robbery,2 armed robbery,3 assault with a dangerous weapon,4 and escape from custody.5 On January 19,1973, a mental competency hearing was held at which Wood was ruled competent to stand trial.
*556At trial, appellant did not contest the essential facts proved by the government. Rather, he relied solely upon the defense of insanity. At the conclusion of the two-day trial, on April 13, 1973, Wood was found guilty on two of the four charges, those of armed robbery (under the D.C.Code) and escape (U.S.Code), whereupon Wood was sentenced to three to nine years’ imprisonment for the armed robbery conviction and twenty months’ to five years’ imprisonment for the escape conviction, to be served concurrently. On May 24, 1973, Wood filed his notice of appeal from the judgment of conviction.
After the filing of this court’s opinion in United States v. DeCoster6 on October 4, 1973 (“Decoster I”), appellant moved for a new trial on the ground that he had been denied the effective assistance of counsel. The trial court denied appellant’s motion, and appellant appealed from that order. On January 3, 1974, this court ordered, sua sponte, that the two appeals filed by Wood — the appeal from his convictions (No. 73-1629) and the appeal from the denial of his motion for a new trial (No. 74-1004)— be consolidated for all purposes.
On September 13, 1974, the appeals were argued before a panel consisting of Chief Judge Bazelon and Judges Robinson and MacKinnon. A week later the court remanded the record to the district court for a supplemental hearing on the issue of trial counsel’s preparation and investigation.
The supplemental hearing ordered by the court was held on November 8, 1974. On March 26, 1975, the district court issued its memorandum opinion, which reviewed the highlights of the testimony at the hearing and contained the following conclusions of law:
1. The defendant has not carried his burden of showing a substantial violation of any of the duties owed by counsel. United States v. DeCoster, supra, 159 U.S.App.D.C. at 333, 487 F.2d at 1204.
2. The defendant received the reasonably competent assistance of Mr. Saccardi acting as his diligent and conscientious advocate. United States v. DeCoster, supra, 159 U.S.App.D.C. at 331, 487 F.2d at 1202.
The parties submitted briefs to this court following the supplemental hearing, and argument was again heard by the original panel on December 17, 1975.
On March 17, 1977, the court, sua sponte, issued an order setting Wood for rehearing by the court en bane, on May 26, 1977, along with the rehearing in Decoster. The court also invited various groups to submit amicus briefs and directed the parties (and invited the amici) to address two specific issues in their briefs:
(1) Counsel’s failure to seek a continuance at the start of the trial upon learning that' the defense psychiatrist would not be accepted as an expert witness.
(2) The need for and role of the expert in preparing for trial as well as testifying at trial in cases involving complex issues like insanity.
The court thereafter issued orders affirming the convictions of Decoster (May 14, 1979) and appellant Wood (June 29, 1979). On July 10, 1979, the en banc court issued opinions in the Decoster case (“Decoster III”).
2. The Issues of Ineffective Assistance of Counsel
The issue presented by Wood and Decoster is whether appellants were afforded the effective assistance of counsel that is guaranteed by the Fifth and Sixth Amendments.7 Although the cases are distinguish*557able on their facts — as are almost all cases raising claims of ineffective assistance of counsel — they may properly be viewed as raising the same legal issue. Upon closer examination, the cases bear other similarities as well.
Appellant in Decoster identified eight general areas in which he thought trial counsel’s performance fell below constitutionally permissible standards. The most significant of the areas was counsel’s failure to interview potential witnesses before trial.8
The instant appeal also raises questions concerning trial counsel’s preparation ‘for trial. In particular, appellant Wood alleges that counsel failed to conduct an adequate factual investigation9 and failed to familiarize himself adequately with the legal principles involved in the presentation of an insanity defense.10 In addition, as already noted, the court sua sponte raised the issue of counsel’s failure to seek a continuance upon learning that Dr. Dabney, whom defense counsel intended to offer as an expert testifying to the existence of defendant’s mental illness, would not be accepted by the court as a person qualified to give an expert opinion. Appellate counsel for the defendant have discussed this as bearing upon a general problem of lack of adequate preparation.
3. The Medical Testimony At Trial
At the outset of the defense case, appellant’s counsel was informed by the court that it did not “customarily accept [Dr. Dabney] as an expert.” The prosecutor developed the information that Dr. Dabney had been dismissed by St. Elizabeths as not fit for the practice of psychiatry in the hospital, and that he had appealed this determination and exhausted his remedies without avail. This left open the possibility that Dr. Dabney could be called as a lay witness because he had observations concerning the behavior and attitude of defendant. However, appellant’s trial counsel, having learned of Dr. Dabney’s dismissal at the trial, chose not to place Dr. Dabney on the stand because in his view, the defense would be harmed by the exposure of Dr. Dabney’s prior background on cross-examination.
Defense counsel proceeded by calling a number of medical witnesses who had examined defendant. These were all members of the staff of St. Elizabeths Hospital. Three witnesses were psychiatrists; Drs. Palacio, Strawinsky, and Robertson; a fourth witness, Dr. Bauer, was a clinical psychologist. Without reviewing the testimony in detail, it may be stated that these witnesses had originally examined defendant in 1970-71 and had diagnosed him as schizophrenic, catatonic type. However, after Wood’s elopement in February 1972, they concurred in a revision of their conclusion, and testified that as of February 1972, he was not mentally ill. The critical testimony was that of the psychiatrist Dr. Robertson. He testified that his original diagnosis was based primarily on appellant’s lack of response, or slow response, to questions and on appellant’s references to gun *558powder and to shooting people. Also, upon arrival at the hospital, Wood scratched his arm with a sharpened tooth brush. There was also testimony that during his stay at St. Elizabeths he had engaged in a number of fights or threats. There was no question of his assaultiveness, but Dr. Robertson concluded that that in itself was not a symptom of mental illness.
Defense trial counsel, in calling Dr. Robertson to the stand, was acting on the theory that the optimal approach from the defense point of view would be an effort to suggest to the jury “that this change in diagnosis was solely motivated by the desire to remove Michael Wood from the confines of St. Elizabeths where he had become too much of a problem.”11 Accordingly, defense trial counsel probed at considerable length for the reasons for the change in Dr. Robertson’s diagnosis. Dr. Robertson’s testimony was that the revised diagnosis of schizophrenia was essentially based on his observation that the symptoms that had been the basis for the original diagnosis of schizophrenia (e. g., preoccupation with guns and shooting people and slowness or hesitancy or response) were not present except when appellant was in front of the doctor. He learned from a number of ward personnel that defendant did not show a preoccupation with guns while on the ward. He consulted with defendant’s mother on three occasions and with his sister and found that they did not confirm the presence of those symptoms. Dr. Robertson also said that neither the mother nor the sister had told him that appellant showed any slowness or hesitancy of response. And apparently the appellant himself had told Dr. Robertson that “he really didn’t believe in the shooting of all these people.” (Tr. at 165.) These factors led Dr. Robertson to the net conclusion that there had been malingering, based in part on what appellant had allegedly said to the doctor.
4. Testimony of Court-Appointed Psychiatrist
A significant feature of this case developed when the court on its own motion ordered the appointment of Dr. Harold Kaufman to examine appellant and to report to the court. At appellate argument government counsel asserted that Dr. Kaufman is reputed to be a defense oriented psychiatrist. A similar assertion appears in the transcript of the remand hearing12 and in briefs filed by the government.13 This was not challenged by appellant or amici curiae. We have no occasion to say whether this condition would have been necessary to our ruling. Certainly it fortifies the conclusion that we have reached.
On the basis of appellant’s behavior during an interview lasting from one and one-half to two hours, an examination of the records, and interviews with nursing assistants, Dr. Kaufman concluded that Wood was not suffering from a mental disorder at the time of examination, nor was he suffering from a mental disorder as of February 28, 1972. Dr. Kaufman gave detailed explanations of the basis for his conclusions, which is fairly summarized by the following excerpt from his testimony at trial:
Well, the evidence was so firm that I believed that I had with respect to his mental condition from, let’s say, January 1, 1972, having three nursing assistants completely agree that he was not particularly ill or showed manifestations of mental illness during that period. His own assertions and the coherence of his own responses to me, his rationality. The evidence was so conclusive that the rather mixed reports which existed which I was familiar with to some extent and his background would not have served to have changed my mind at all with respect to the specific question which was being placed upon me, to weigh his state of mind at the time of the offense. [Tr. 216-17]
*5595. Applications of Rulings of Decoster III
While in Decoster III there were three different opinions in support of affirmance of the conviction, and there was no majority opinion for the court, it is fair to state the outcome of that case in these terms: A majority of the judges agree that the “claimed inadequacy must be a serious incompetency that falls measurably below the performance ordinarily expected of fallible lawyers.” (Quoted from plurality opinion by Judge Leventhal; at 208). Although there are differences in formulation, there is no difference in substantive content in the opinion of Judge MacKinnon, which states that the defendant must show a “substantial breach” in the duty owed to defendant by counsel.
In addition, a majority of the court is of the view that defendant does bear the burden of showing that counsel’s substantial breach was likely to have resulted in prejudice to appellant’s case. That is the formulation in Judge Leventhal’s opinion. At 208. It is necessarily included in the burden assigned to defendant in Judge MacKinnon’s opinion: that defendant show that he actually “suffered unfair prejudice” as a result of counsel’s breach. At 320, 321.
The court is of the view that appellant Wood does not make a showing that is sufficient under the Decoster rulings to lay a foundation for relief on the basis of ineffective assistance of counsel.
Amicus curiae stress that defense trial counsel had never before presented an insanity defense. He had prepared for the case by reading the most recent ruling of this court on the insanity defense;14 Law and Tactics in Federal Criminal Cases (Shadoan, ed. 1966), which contained a chapter on the insanity defense; and materials from the Criminal Practice Institute. In addition, he reviewed the hospital records, spoke to his client, and spoke to the doctors at the hospital. So far as the trial presentation is concerned, the court is of the view that under the circumstances that confronted him, defense counsel developed a rational theory in an effort to secure an acquittal in the face of adverse medical opinions. It was a theory that might have been successful.
Perhaps the most damaging feature of the trial from the defense point of view was the rebuttal testimony of Dr. Kaufman, called by the prosecution. It could not vigorously be asserted that this court-appointed expert was motivated by desire to remove a troublesome personality from the hospital’s jurisdiction.
Dr. Kaufman’s testimony negates the likelihood of any prejudice to the defendant, and indeed fairly establishes that prejudice was improbable.
In order to secure a reversal, appellant must establish some basis for believing that a different kind of preparation would have resulted in the presentation of a contrary line of testimony for the jury’s consideration. It would be extraordinarily difficult, if not impossible, to bring on a psychiatrist long after the event to reconstruct a mental condition that existed in 1972. But the court-appointed psychiatrist who made his examination on October 5, 1972, felt able to give an expert opinion as to defendant’s condition in February 1972.
Appellant’s counsel rightly stress that defense counsel was not aware prior to trial of the dismissal from St. Elizabeths of his proposed expert witness, Dr. Dabney. This feature is troublesome. In extenuation, it should be noted that Dr. Dabney had been retained by appellant’s family, in connection with other offenses, in 1971, prior to the date of offense and, of course, prior to the court’s appointment of trial counsel. It was as the family-retained psychiatrist that Dr. Dabney first examined appellant in 1971.
We have no need to determine whether defense trial counsel’s lack of pretrial awareness of Dr. Dabney’s weaknesses fell short of the pertinent standard of effectiveness. Even if such a shortfall be as*560sumed, we are clear that there has been a lack of indication that it was a likely source of prejudice to the defendant.
6. Vacation of the Federal Court
The court’s order of affirmance of June 29, 1979, was based on this court’s conclusion that there has been no showing of denial of effective assistance of counsel. In addition to the claim that he was denied the effective assistance of counsel, however, Wood challenges his conviction on equal protection grounds. This challenge arises out of the trial court’s instruction, based upon 24 D.C.Code § 301(j) (1973), that the burden of proof on this issue of insanity falls upon the defendant. The court charged:
The burden of proof is on the defendant to establish by a fair preponderance of the evidence that as a result of mental disease he either lacked substantial capacity to conform his conduct to the requirements of the law or lacked substantial capacity to appreciate the wrongfulness of his conduct.
The contention is that section 301(j) violates the equal protection clause in that it puts a burden on defendants in the District of Columbia that is different from that resting upon defendants in all other federal district courts. The government’s brief contends that the issue of constitutionality was decided adversely to appellant in United States v. Greene.15 However, the Greene case involved the violation of the D.C.Code, and it expressly put to one side the issue whether the burden of proof could be shifted when defendant is charged with a violation of title 18 of U.S.Code.
This court has now decided, in the case of United States v. Powell,16 that 18 U.S.C. § 751(a) does not apply to a patient who escapes from St. Elizabeths Hospital, having been confined there upon his acquittal in a prior criminal case by reason of insanity. The Powell ruling is properly applied to the Wood case since Wood’s conviction was pending appeal at the time Powell issued.17 Accordingly, Wood’s conviction for violating 18 U.S.C. § 751(a) is reversed.
The court recalls its mandate in order to modify its affirmance order of June 29, 1979, so as to provide that the judgment of conviction of violation of 18 U.S.C. § 751(a) is reversed, and that the sentence imposed upon conviction of 22 D.C.Code §§ 2901, 3202 is affirmed.
So ordered.
MacKINNON, Circuit Judge(separate opinion):
The dissenters attempt to construe “prejudice” and “likelihood of prejudice” so that the likelihood of prejudice will prevail, but the prevailing opinions in Decoster and the per curiam opinion here do not support such a construction. The nature of the prejudice will vary with the circumstances of each case and what is sufficient prejudice must be evaluated in the context of varying facts, so any “likelihood of prejudice” cannot be the ultimate test. Human imagination, and some judicial imagination, as Decoster proves, can always conjure up some far-fetched likelihood in almost any case. So just likelihood of prejudice is not the test.
The rule in the United States courts of law is that the prejudice that must be shown must affect the “substantial rights of the [party].” The applicable United States Statute provides:
On the hearing of any appeal or writ of certiorari in any case, the court shall give judgment after an examination of the record without regard to errors or defects which do not affect the substantial rights of the parties.
28 U.S.C. § 2111. (Emphasis added) The Federal Rules of Criminal Procedure provide:
*561(a) Any error, defect, irregularity or variance which does not affect substantial rights shall be disregarded.
(b) Plain errors or defects affecting substantial rights may be noticed although they were not brought to the attention of the court.
F.R.Crim.P. 52.
So regardless of how the test is articulated it always has to add up to the same thing, to wit, that if the questioned conduct did not “affect substantial rights, [it] shall be disregarded.”
. United States v. Decoster, 624 F.2d 196, (D.C. Cir. 1979).
. See 22 D.C. Code § 2901 (1973).
. See id. at §§ 2901, 3202.
. See id. at § 502.
. See 18 U.S.C. § 751(a) (1976).
. 159 U.S.App.D.C. 326, 487 F.2d 1197 (1973).
. The Fifth Amendment states that “[n]o person shall ... be deprived of life [or] liberty . . . without due process of law,” while the Sixth Amendment more specifically provides that “the accused shall enjoy the right to have the Assistance of Counsel for . his defence.” An appellant’s claim that he was denied the effective assistance of counsel implicates both amendments, although “[t]he Sixth Amendment has overlapping but more stringent standards than the Fifth Amendment,” Scott v. United States, 138 U.S.App.D.C. 339, 427 F.2d 609, 610 (1970).
. The other general areas of allegedly substandard performance were (1) counsel’s slowness in seeking a bond review, (2) his failure to obtain a transcript of appellant’s preliminary hearing, (3) his announcement of “ready” for trial before having fully developed the defense, (4) his waiver of a jury trial, (5) his decision to allow defendant to be tried before the judge before whom Decoster’s co-defendants pleaded guilty, (6) his failure to make an opening statement, and (7) his failure to see that Decoster’s sentence was properly executed.
. Appellant cites four examples of counsel’s alleged failure to conduct an adequate factual investigation: (1) his failure promptly to obtain an independent psychiatric examination, (2) his failure to obtain psychiatric assistance that was available and necessary for the preparation of the insanity defense, (3) his failure to investigate and use sources of lay testimony on the issue of insanity, and (4) his failure to consult with the medical witnesses that he intended to call at trial.
. Appellant claims (1) that counsel was unfamiliar with the legal rules relating to expert testimony and its role and scope in an insanity trial, (2) that counsel was unaware of the rules relating to hearsay testimony by expert witnesses, and (3) that counsel was fundamentally unaware of the decisional law relating to the insanity defense in this jurisdiction.
. Trial transcript, p. 33.
. Remand transcript, p. 172.
. Appellee’s Supplemental Memorandum (filed October 20, 1975, at 3; Supplemental Memorandum of Appellee on Rehearing En Banc, (filed May 20, 1975), at 3.)
. United States v. Brawner, 153 U.S.App.D.C. 1, 471 F.2d 969 (1972).
. 160 U.S.App.D.C. 21, 29, 489 F.2d 1145, 1153 (1973), cert. denied, 419 U.S. 977, 95 S.Ct. 239, 42 L.Ed.2d 190, rehearing denied, 419 U.S. 1041, 95 S.Ct. 530, 42 L.Ed.2d 318 (1974).
. 164 U.S.App.D.C. 104, 503 F.2d 195 (1974).
. See United States v. Snyder, 174 U.S.App. D.C. 117, 118, 529 F.2d 871, 872 (1976).