BLACKMUN, Circuit Judge.
This habeas corpus case, instituted by Gale H. Johnson, an Iowa state prisoner now 64 years of age, and primarily concerning the frequently contested but consistently approved Iowa alibi instruction, is before us a second time.1
[51]*51Johnson is serving a life sentence2 in the Iowa penitentiary as a result of his conviction by a jury of murder in the second degree, as defined by § 12912 of the 1939 version of the Iowa Code. The victim, a police officer, was shot on the early morning of May 27, 1934, as he was investigating a burglary of a Burlington store. On appeal Johnson’s conviction was unanimously affirmed by the Supreme Court of Iowa. State v. Johnson, 221 Iowa 8, 264 N.W. 596, 267 N.W. 91 (1936).
Judge Oscar Hale, who presided at Johnson’s 1934 state trial, gave the jury instructions which consume 18 pages of the transcript. Those instructions contain numerous references, at least 13 by our count, to the effect that the state had the burden of establishing the material charges of the indictment, including time and place, beyond a reasonable doubt, that “the innocence of the defendant will be presumed”, that the jury’s determination is to be made in the light of all the evidence, and the like. But they also contain the particular alibi instruction now challenged.3 The defense, in its post-trial motion, excepted to this instruction on the grounds, among others, that it “does not correctly state the law with reference to the defense of alibi.” This was overruled by Judge Hale.
On appeal the Supreme Court of Iowa said, 264 N.W. at 602:
“An alibi is an affirmative defense; the burden of proof is upon the person setting up an alibi to prove it by a preponderance of evidence. Of course, if the whole record raises a reasonable doubt of his guilt, he may be found not guilty. The instructions in this case in regard to the alibi did not go as far as such instructions many times rightfully go. The court might very well have told the jury, in addition to what he said about an alibi, that the evidence of an alibi should be scanned with caution; that it is a defense easily manufactured.”
As noted above, this language is that of a unanimous court.
Johnson’s present application for federal habeas relief, after denial by the district court, came before a panel of this court in 1967. Three specific due process issues were raised: (1) the use of allegedly false evidence at Johnson’s state trial; (2) the claimed purposeful suppression by the state of impeachment testimony by a defense witness named [52]*52Orsucci,. since deceased; and (3) the impropriety, generally and constitutionally, of the alibi instruction which, it was argued, served to shift the burden of proof as to the alibi to the defendant and thus to destroy the fundamental presumption of innocence. Our panel, after careful study and with a detailed opinion, decided each of these issues, as well as a general claim of denial of a fair trial, adversely to the petitioner. Johnson v. Bennett, 386 F.2d 677 (8 Cir. 1967).
Our panel pointed out that this court, 50 years before, had reversed a federal conviction because of the use of such an alibi instruction, Glover v. United States, 147 F. 426, 430-433 (8 Cir. 1906); that the Iowa court, although at times sharply divided, had consistently upheld an instruction of this type; that, when Johnson’s case was tried in 1934, over three decades ago, the instruction “had the full backing of the Iowa Supreme Court”; that Johnson’s conviction “was finally adjudicated long before the [United States] Supreme Court determined federal constitutional rights guaranteed by the first ten amendments are to be applied to state proceedings by reason of the Fourteenth Amendment”; that the defendant, at his trial and on his appeal, had made no challenge to the instruction on constitutional grounds; that there was “little doubt that such challenge, if then made, would have been rejected”; and that it did not believe that the present challenge, even if “entitled to be upheld under present day standards, would be given retroactive application to the 1934 conviction.”
After the panel’s decision Johnson filed a petition for certiorari with the Supreme Court of the United States. Certiorari was granted. 390 U.S. 1002, 88 S.Ct. 1247, 20 L.Ed.2d 102.
Prior to the argument of Johnson’s case in the Supreme Court, the Iowa alibi instruction’s due process aspect was once again presented to this court, this time by Ronald Maurice Stump, another state prisoner seeking federal habeas relief. Stump had been convicted of second degree murder in 1961 and had received and was serving a sentence of 75 years. His sole defense was an alibi. In his state trial the jury had been instructed that the defendant must establish the alibi by a preponderance of the evidence but that the burden of proof beyond a reasonable doubt as to the case as a whole was on the state. Stump’s conviction was affirmed by the Iowa Supreme Court by a divided (5-3) vote. State v. Stump, 254 Iowa 1181, 119 N.W.2d 210 (1963). Certiorari was denied. 375 U.S. 853, 84 S.Ct. 113, 11 L.Ed.2d 80.
In his federal habeas petition Stump raised the due process issue with respect to the alibi instruction and also questioned Iowa Code § 777.18 in its application to him. The district court denied the petition. We heard the case en banc and by a divided vote concluded that, in Stump’s case, the Iowa rule as to the burden of proof on the alibi reached the level of constitutional error and was vio-lative of the 14th Amendment’s due process clause. Stump v. Bennett, 398 F.2d 111 (8 Cir. 1968). Judge Lay, in speaking for the majority of five judges, cited Morrison v. California, 291 U.S. 82, 54 S.Ct. 281, 78 L.Ed. 664 (1934), and other eases and distinguished the defense of alibi from the plea of insanity considered in Leland v. Oregon, 343 U.S. 790, 72 S.Ct. 1002, 96 L.Ed. 1302 (1952). He necessarily made reference to the panel decision in Johnson v. Bennett and to the then pending grant of certiorari in Johnson’s case and observed :
“The Johnson case concededly has some factual distinctions from the present one. Also significant is the fact that in the Stump case, unlike Johnson, counsel has carefully preserved by objections throughout the trial and appellate procedures his argument as to the unconstitutionality of the instruction.” 398 F.2d at 122-123.
The three judges who had comprised the Johnson panel dissented in Stump. In two separate opinions, 398 F.2d at [53]*53123 and 128, they (a) agreed that alibi is not an affirmative defense; (b) agreed that an instruction placing the burden on the defendant to establish alibi by a preponderance of the evidence is erroneous; (e) observed that “due process permits the state a wide range in developing rules of procedure and evidence”; (d) felt that Stump’s instructions, “when * * * fairly considered as a whole”, gave him “the full benefit of the presumption of innocence”; (e) noted that “on at least twelve different occasions” the Stump jury was told that it “was required to determine beyond a reasonable doubt that defendant had committed the offense before it could find him guilty”; (f) said that Leland v. Oregon “affords strong support for an affirmance here”; (g) characterized the alibi evidence in Stump’s case as “extremely weak”; and (h) stated that the right given the state to retry Stump was of doubtful value in view of the passage of 7 years since the commission of the crime.
Four months later Johnson’s case was argued in the Supreme Court. The Court soon issued its opinion, per cur-iam, but with Mr. Justice Black dissenting without other comment, vacating this court’s panel decision and remanding the ease “for reconsideration” by us “[i]n view of” our en banc holding in Stump. Johnson v. Bennett, 393 U.S. 253, 89 S.Ct. 436, 21 L.Ed.2d 415 (1968). On the same day the Supreme Court, with three Justices voting otherwise, denied certiorari in Stump’s case. 393 U.S. 1001, 89 S.Ct. 483, 21 L.Ed.2d 466 (1968).
In the light of this history we felt it advisable to have our reconsideration of Johnson’s case en banc with supplemental briefing and reargument. This has been done.
We turn initially to the Iowa decisions.
We have read with interest the many Iowa cases where the alibi instruction was under challenge. The very number of the cases, and the constant resubmission of the issue to the court, indicate the concern which the instruction has occasioned. Although the Iowa court has been unanimous in opinion in a large majority of its cases, the court was split in its early opinions and again has been split in the most recent ones. In the intervening unanimous opinions there are, nevertheless, some indications of struggle in the decisional process.
Apparently the source ease is State v. Vincent, 24 Iowa 570 (1868). The charge was murder. The defense asserted an alibi and, as well, that the victim was not the person named by the state. The court placed the burden of proof as to both issues upon the defense. “These defenses, then, must be sustained by the prisoner, and the evidence necessary to sustain either of them must be sufficient to outweigh the proof tending to establish its contradictory hypothesis.” 24 Iowa at 578. In the next two cases, both resulting, incidentally, in reversals of convictions, minority disagreement with the Vincent rule is expressed. State v. Hardin, 46 Iowa 623 (1878); State v. Northrup, 48 Iowa 583 (1879). Then in State v. Red, 53 Iowa 69, 4 N.W. 831, 832-833 (1880), the court stated that the defense was required to prove an alibi by a preponderance of the evidence but that this “does not abrogate the doctrine of reasonable doubt” which “extends to all the evidence.” See, also, State v. Kline, 54 Iowa 183, 6 N.W. 184 (1880).
The Iowa court came clearly to grips with the problem in the frequently cited case of State v. Hamilton, 57 Iowa 596, 11 N.W. 5 (1881). There, the Vincent doctrine, by a 3-2 vote, was held to be “the settled law of the state.” The dissent, pp. 6-7, observed that reasonable doubt may be raised by evidence “which could not be said to preponderate”; that “[b]oth rules [preponderance as to alibi and reasonable doubt overall] cannot be correct, because they are inconsistent with each other”; that “[n]o jury can follow both”; that the majority position “requires a modification of the rule as to the presumption of innocence”; and that the majority are mis[54]*54led by the suspicion which attaches to evidence of an alibi. State v. Krewsen, 57 Iowa 588, 11 N.W. 7 (1881), decided the same day, approved the instruction on the ground that the case was controlled by Hamilton. A division in the court’s vote is also apparent in State v. Reed, 62 Iowa 40, 17 N.W. 150, 151 (1883) (3 to 2); State v. Rivers, 68 Iowa 611, 27 N.W. 781, 784 (1886) (3 to 2); and State v. Maher, 74 Iowa 77, 37 N.W. 2, 4 (1888) (“a majority”).
After Hamilton was decided in 1881 and with the exception of the divisions noted in the Reed, Rivers and Maher cases just cited, there followed a long period of approximately 80 years during which the Iowa court consistently and repeatedly approved the alibi instruction with its allocation of burden of proof. We cite in the footnote the numerous cases which we have found which approve the instruction generally or by inference, by flat holding or by dictum.4 In certain of these cases, however, some discomfort with the situation is evident. Thus in State v. Matheson, 130 Iowa 440, 103 N.W. 137, 141 (1905), the court characterized its approval of the instruction as “a somewhat anomalous rule.” In State v. Thomas, 135 Iowa 717, 109 N.W. 900, 902 (1906), writ of error dismissed, 215 U.S. 591, 30 S.Ct. 407, 54 L.Ed. 340, the court referred to its holding as “in some respects peculiar to this state.” In State v. Bosworth, 170 Iowa 329, 152 N.W. 581, 586 (1915), the court observed, “It is none too clear what is meant by the rule * * *." And in State v. Wagner, 207 Iowa 224, 222 N.W. 407, 410, 61 A.L.R. 882 (1928), it observed, “We have not seen a satisfactory rationale of the law of alibi and shall not undertake to formulate one.”5
[55]*55It is of interest to note, too, that the Iowa court frequently struggled in these cases with the subsidiary question as to whether evidence was of an alibi, which would then justify the instruction, or was merely in opposition to the state’s primary ease. See, for example, State v. Steffen, 210 Iowa 196, 230 N.W. 536, 538, 78 A.L.R. 748 (1930), and State v. Dunne, 234 Iowa 1185, 15 N.W.2d 296, 300 (1944). The issue was often also confused by the precautionary or disparagement instruction customarily given in Iowa to alibi evidence.6
The most recent Iowa cases again reveal a split vote. In State v. Stump, supra, 254 Iowa 1181, 119 N.W.2d 210 (1963), the court divided 5 to 3 with a vigorous dissent championing the dissenting point of view expressed in 1881 in Hamilton. In State v. Agee, 257 Iowa 1345, 136 N.W.2d 419, 421 (1965), the opinion observed, “A majority * * * of this court are still of the view * * * the instruction as given is correct.” In State v. LaMar, 260 Iowa 957, 151 N.W.2d 496 (1967), the vote was 6 to 3 with the writer of the majority opinion stating, p. 504, that Stump for him was controlling but that had he been a member of the court at the time of that decision he would have joined the dissent there. In State v. Carter, Iowa, 161 N.W.2d 722 (1968), the vote was 5 to 4 with the majority suggesting, p. 727, that trial courts “omit from the alibi instruction that part which puts the burden on defendant of proving an alibi by a preponderance of evidence.” However, the court’s “long established rule on alibi” was not overruled “at this time.” Finally, in State v Galloway, Iowa, 167 N.W.2d 89, decided April 8, 1969, the court referred to the rulings by this court and by the United States Supreme Court in Stump and in Johnson and said, p. 96, “Pursuant to these pronouncements and mandates by the United States courts the alibi instruction can no longer be approved.” That appellant’s murder conviction was reversed and the case was remanded. Two justices concurred in the result.
It is thus apparent that the Iowa court has continuously struggled with the alibi instruction so frequently employed by the trial courts of the state. The division among the members of the Supreme Court was clear and bitter in the earlier cases of 80 years ago. The division has been clear and bitter in the cases decided during the last 6 years.
The Iowa ruling seems to have been based on the notion, apparent from certain of the opinions, that alibi, as insanity, is an affirmative defense or excuse rather than a part of the prosecution’s own case. State v. McCumber, 202 Iowa 1382, 212 N.W. 137 (1927); State v. Rourick, 245 Iowa 319, 60 N.W.2d 529, 531 (1953); State v. Stump, supra, 119 N.W.2d at 218. The dissent in Stump, 119 N.W.2d at 228-229, points out the logical difficulty with this.
With this as background, a majority of this court now concludes that there is sufficient merit in Johnson’s claim of deprival of constitutional due process as to require the honoring of his application for federal habeas relief. We so conclude because:
1. As noted above, we recognized in Stump, 398 F.2d at 122, that Johnson’s case “concededly has some factual distinctions” from Stump’s. Further, the dissent in Stump, 398 F.2d at 127, characterized the evidence in support of Stump’s alibi as “extremely weak.” Now that the Supreme Court’s remand for reconsideration compels us to take the measure of these factual differences [56]*56between the two cases, we hold that they possess no legal significance.
2. Our conclusion and holding in Stump, that his Iowa alibi instruction was violative of constitutional due process in that it shifted the burden of proof to him and deprived him of the presumption of innocence, and that its use was not harmless error, necessarily control Johnson’s case. Indeed, our judges who dissented in Stump even considered Stump’s instructions “somewhat stronger with respect to preserving * * * constitutional rights” than Johnson’s instructions. 398 F.2d at 126. That Johnson’s prosecution gave the alibi rule great emphasis and full power is evident from its closing argument to the jury.7
3. Although, as far as we can tell from the somewhat restricted record now available of the 1934 state trial, no challenge was made by Johnson’s defense to the alibi instruction on specific constitutional grounds, the instruction nevertheless was vigorously challenged.8 We have noted above that the instruction was argued to arid passed upon by the Supreme Court of Iowa. 264 N.W. at 602. Thus the propriety of the instruction was strongly contested at trial and on the state appeal. We recognize that even a constitutional claim, under appropriate circumstances, may be the subject of waiver in the state courts. Fay v. Noia, 372 U.S. 391, 438-439, 83 S.Ct. 822, 9 L.Ed.2d 837 (1963). Although, in contrast, it may be true that the defense in Stump at all stages preserved constitutional objections to the instruction, we could not hold, in good conscience, that Johnson, who so vigorously challenged the alibi instruction throughout his state proceedings 35 years ago, knowingly waived what the Constitution guaranteed to him. In Kaufman v. United States, 394 U.S. 217, 89 S.Ct. 1068, 22 L.Ed.2d 227 (1969), a case emanating from the Eighth Circuit, the Supreme Court very recently cautioned us that the failure to raise a constitutional claim on direct appeal does not deprive a federal post-conviction court of power to adjudicate the merits of that constitutional claim. In footnote 3 of the opinion, 394 U.S. at [57]*57220, 89 S.Ct. 1068, the suggestion is made that the real question is whether the case is one in which a court’s refusal to act would be appropriate. In view of the implications of Kaufman we must reject any suggestion of waiver. See also Johnson v. Zerbst, 304 U.S. 458, 464, 58 S.Ct. 1019, 82 L.Ed. 1461 (1938); Fay v. Noia, supra, 372 U.S. at 439, 83 S.Ct. 822, 9 L.Ed.2d 837; Brookhart v. Janis, 384 U.S. 1, 4, 86 S.Ct. 1245, 16 L.Ed.2d 314 (1966).
4. As pointed out in Stump, 398 F.2d at 122, our holding there that an oppressive shifting of the burden of proof to the defendant violates due process is not a new constitutional doctrine. Thus we were not “directly faced with issues of retroactivity.” The dissent in Stump seems to suggest that the question of ret-roactivity is in the case. 398 F.2d at 126. This was definitely so stated in the panel’s decision in Johnson’s case. 386 F.2d at 682-683. We adhere, however, to the majority view in Stump that we are not faced in Johnson’s case with an issue of retroactivity. Even if we were, it would perhaps suffice only to note that Johnson’s case, with its alibi instruction issue, reached us before Stump’s.
5. The integrity of Johnson’s trial and conviction remains seriously clouded by the allegations, seemingly not now controverted, of a sheriff’s erroneous, if not false, report and return as to the whereabouts and unavailability of an actually available but imprisoned defense witness, and of the state’s use of handwriting evidence now conceded questionable even by the state’s own present expert.
6. The Supreme Court of Iowa, by its holding in State v. Galloway, supra, although made under the press of our decision in Stump and, more heavily, of the Supreme Court’s, remand in Johnson’s ease, has now ruled that the use of the Iowa alibi instruction “can no longer be approved” and requires, on direct appeal, a reversal of the conviction. Thus the Iowa law is not now what it was said to be at the time of Johnson’s direct appeal.
The State of Iowa, of course, as with Stump, is entitled to a reasonable time to retry Johnson for the crime with which he has been charged. We realize that in Johnson’s case, with the passage of 35 years, more so than in Stump’s, there is little likelihood of the state’s ability to retry. Witnesses probably are gone and memory undoubtedly has dimmed. To the extent the time factor has dampened the state’s ability to retry it also serves to increase the injustice done to Johnson if, by chance, he is innocent of the crime of which he was accused.
This is not an easy case for a federal court. We entertain a natural reluctance to interfere with the standards and the judicial processes of a sovereign state. Federal constitutional rights, however, are precious rights and, even at a late date, their observation and enforcement are demanded.9 An ordered society deserves no less.
If retrial of Johnson is not under way in an appropriate state court within 6 months from the date of issuance of our mandate, the district court is to grant Johnson’s petition for a writ of habeas corpus. Of course, we expect the prosecution, if, for any reason, it concludes not to retry Johnson, promptly (and, hopefully, within 30 days of the issuance of our mandate) to advise the federal district court and the penitentiary authorities of that decision so that Johnson’s release forthwith may then be effected without waiting for the stated 6-month period to expire.
The district court’s decision is vacated and the case is remanded for further [58]*58proceedings in conformity with this opinion.