dissenting:
The majority’s holding that appellant’s conviction was not violative of due process rests, as I understand it, on three alternate conclusions: First, that the rule of Wardius v. Oregon, 412 U.S. 470, 93 S.Ct. 2208, 37 L.Ed.2d 82 (1973), should not be applied retrospectively; second, that even if Wardius were to be applied retrospectively, and appellant therefore held entitled to reciprocal discovery, here the denial of such discovery was harmless error; and third, that in any case, appellant got reciprocal discovery. For the reasons that follow, I disagree with all three of these conclusions. I therefore dissent.
—1—
The Facts
After being convicted by a jury of rape, appellant was sentenced on May 29, 1969, to ten to twenty years in prison. On October 30, 1969, we affirmed. 216 Pa.Super. 744, 258 A.2d 337. On January 10, 1970, the Supreme Court denied appellant’s petition for allowance of appeal. On September 13, 1974, appellant filed a petition under the Post Conviction Hearing Act1 in which he contended that Wardius v. Oregon, 412 U.S. 470, 93 S.Ct. 2208, 37 L.Ed.2d 82 (1973), requires that he be awarded a new trial. After a hearing the lower court denied appellant’s petition.
Appellant’s principal defense at trial was an alibi. In order to be able to present that defense, appellant’s counsel *26complied with Pa.R.Crim.P. 3122 and before trial gave notice to the Commonwealth of his intention to present the defense of alibi, identifying the witnesses he intended to offer in support of the alibi. The notice was given under protest, appellant’s counsel objecting to Rule 312 as violative of the United States and the Pennsylvania Constitutions. The Commonwealth in preparing for trial used the information supplied in the notice;3 it did not, however, disclose to *27appellant’s counsel the identity of the witnesses it intended to call to rebut appellant’s alibi.
—2—
The Rule of Wardius
In Wardius, the United States Supreme Court reviewed an Oregon statute that was very similar to Rule 312.4 There the defendant had been prevented from testifying concerning an alibi, and the testimony of an alibi witness was stricken because of failure to give the pre-trial notice required by the statute. The Court noted that while the statute obliged the defense to disclose its strategy and witnesses, it did not impose a reciprocal obligation on the prosecution. This disparity in pre-trial discovery, the Court held, made enforcement of the statute unconstitutional as a denial of due process:
It is fundamentally unfair to require a defendant to divulge the details of his own case while at the same time subjecting him to the hazard of surprise concerning refutation of the very pieces of evidence which he disclosed to the State.
412 U.S. at 476, 93 S.Ct. at 2212.
Accordingly, the Court said:
We hold that the Due Process Clause of the Fourteenth Amendment forbids enforcement of alibi rules unless reciprocal discovery rights are given to criminal defendants. 412 U.S. at 472, 93 S.Ct. at 2211.
*28This reasoning has been found by the Pennsylvania Supreme Court to require striking down Rule 312 as unconstitutional since that rule also did not provide for reciprocal discovery. Commonwealth v. Contakos, 455 Pa. 136, 314 A.2d 259 (1974). Since Contakos it has been regularly held that the fact that Rule 312 was enforced during trial requires reversal. Commonwealth v. Jackson, 457 Pa. 79, 319 A.2d 161 (1974); Commonwealth v. Diana, 455 Pa. 267, 314 A.2d 262 (1974); Commonwealth v. Jones, 233 Pa.Super. 52, 335 A.2d 444 (1975), allocatur denied; Commonwealth v. Horace, 226 Pa.Super. 531, 323 A.2d 895 (1974).
The conclusion cannot be escaped that the present case is within the rule of Wardius.5 Appellant was obliged by Rule 312 “to divulge the details of his own case,” without any reciprocal obligation of disclosure being imposed on the Commonwealth, with the result that appellant was “subjected] ... to the hazard of surprise concerning refutation of the very pieces of evidence which he disclosed to the State.”
The Commonwealth contends that this case is distinguishable from Wardius in that here, appellant complied with the requirement of the alibi notice rule and was therefore permitted to present his alibi defense, whereas in Wardius, the defendant was precluded from offering an alibi defense because the alibi notice statute had not been complied with. Rather than being distinguishing, this difference makes Wardius especially applicable. After holding the Oregon statute violative of due process because it did not provide reciprocal discovery, the Court in Wardius had to decide whether the defendant had been prejudiced by the statute since he had not complied with it. The Court summarily dismissed the argument that the defendant might have been granted reciprocal discovery, even though not provided in *29the statute, if only he had given the required notice. The Court held that the statute did not provide for reciprocal discovery and that the defendant had merely taken the legislature at its word. No such problem exists here. Here, the potentially harmful result of a non-reciprocal alibi notice rule has actually occurred: appellant (unlike the defendant in Wardius) complied with the rule; he made discovery, and was denied reciprocal discovery. Thus the facts here fit the rule of Wardius better than the facts in Wardius did. In addition, and perhaps more to the point, the rule of Wardius has been applied to a situation precisely like appellant’s. Commonwealth v. Jackson, 457 Pa. 79, 319 A.2d 161 (1974).
—3—
The failure to comply with Wardius
The majority stresses the fact that appellant was informed of the witnesses that the Commonwealth would present in its case in chief, since the names of those witnesses had been listed on the indictment. Thus, the majority argues, there was de facto reciprocal discovery. However, there was not. Several rebuttal witnesses were called by the Commonwealth whose names were not listed on the indictment. (PCHA Hearing, N.T. 26) “Reciprocity . is the key to Wardius." Commonwealth v. Jackson, supra 457 Pa. at 82, 319 A.2d at 163. When one side says, “I will prove Fact A by calling Witness X,” the other side must reply, “I will counter, and disprove Fact A, by calling Witness Y.” Without such a reply there is no reciprocity:
Due process requires that if an accused is compelled to comply with a notice of alibi rule, then the Commonwealth must reciprocate and provide the names and addresses of all witnesses who will be called to refute an accused’s alibi, regardless of whether the witnesses will be called in rebuttal or in the Commonwealth’s case in chief. See 412 U.S. at 474-76, 93 S.Ct. at 2212-13 [Wardius].
Commonwealth v. Jackson, supra 457 Pa. at 82, n. 4, 319 A.2d at 163, n. 4 (emphasis added).
*30While one decision by this court has indicated that a finding of a Wardius violation requires reversal without more, Commonwealth v. Horace, 226 Pa.Super. 531, 323 A.2d 895 (1974), other decisions make it clear that a harmless error test is appropriate. Commonwealth v. Jackson, supra; Commonwealth v. Jones, 223 Pa.Super. 52, 335 A.2d 444 (1975), allocatur denied. Here I am unable to find as the majority does that the Commonwealth’s failure to afford appellant reciprocal discovery was harmless beyond a reasonable doubt. Chapman v. California, 386 U.S. 18, 87 S.Ct. 824, 17 L.Ed.2d 705 (1967); Commonwealth v. Rodgers, 472 Pa. 435, 372 A.2d 771 (1977) (where cumulative evidence was “wholly unnecessary,” error in admitting it harmless beyond a reasonable doubt; Chapman applied). Because of the Commonwealth’s failure, the defense was unable to prepare possible cross-examination and impeachment of the Commonwealth’s rebuttal witnesses. It is the Commonwealth’s burden to show that no prejudice to the defense resulted. Neither the Commonwealth, nor the majority, has made that showing.
-4^-
Retrospective Application of Wardius
Appellate courts are often required to decide whether and how a new rule of constitutional dimensions is to be applied to cases that arose before the announcement of the rule. In its purest form the question of retrospective application arises in the context of a case where the defendant has been convicted and has exhausted all appellate remedies before the announcement of the rule.6 This is such a case.
*31The United States Supreme Court has often dealt with the problem of retrospective application but has declined to set out a fixed standard for determining when such application is required. In Stovall v. Denno, 388 U.S. 293, 87 S.Ct. 1967, 18 L.Ed.2d 1199 (1967), the Court summarized the factors that should be considered:
The criteria guiding resolution of the question implicate (a) the purpose to be served by the new standards, (b) the extent of the reliance by the law enforcement authorities on the old standards, and (c) the effect on the administration of justice of a retroactive application of the new standards.
388 U.S. at 297, 87 S.Ct. at 1970.
Foremost among these factors is the purpose to be served by the new rule. Desist v. United States, 394 U.S. 244, 249, 89 S.Ct. 1030, 22 L.Ed.2d 248 (1969). I believe that the purpose to be served by the rule of Wardius requires retrospective application.
It is true that before Wardius this court had held that Rule 312 was constitutional. Commonwealth v. Phoenix, 217 Pa.Super. 121, 268 A.2d 460 (1970); Commonwealth v. Vecchiolli, 208 Pa.Super. 483, 224 A.2d 96 (1966). Here the Commonwealth may well have relied on those decisions in seeking strict enforcement of the rule, and in refusing to give reciprocal discovery. While we cannot fault the Commonwealth for failing to anticipate the decision in Wardius when we also failed to anticipate it, that fact is of no consequence when a defendant has been deprived of due process of law.
In considering whether retrospective application is required, it is important to note the nature of the new rule in question.
When the rule is an exclusionary or prophylactic rule the United States Supreme Court has held that retrospective application is not required. In Linkletter v. Walker, 381 U.S. 618, 85 S.Ct. 1731, 14 L.Ed.2d 601 (1965), the Court *32denied retrospective application of the rule of Mapp v. Ohio, 367 U.S. 643, 81 S.Ct. 1684, 6 L.Ed.2d 1081 (1961), that evidence obtained in violation of the Fourteenth Amendment must be excluded as evidence at trial. In Tehan v. Shott, 382 U.S. 406, 86 S.Ct. 459, 15 L.Ed.2d 453 (1966), the Court denied retrospective application of the rule of Griffin v. California, 380 U.S. 609, 85 S.Ct. 1229, 14 L.Ed.2d 106 (1965), that the Fifth Amendment precluded adverse comment by the prosecution or the trial judge concerning a defendant’s invocation of his right not to testify. In Johnson v. New Jersey, 388 U.S. 719, 86 S.Ct. 1772, 16 L.Ed.2d 882 (1966), the Court denied retrospective application of the rule of Miranda v. Arizona, 384 U.S. 436, 86 S.Ct. 1602, 16 L.Ed.2d 694 (1966), and in Stovall v. Denno, supra, of the rule of United States v. Wade, 388 U.S. 218, 87 S.Ct. 1926, 18 L.Ed.2d 1149 (1967), that identification evidence tainted by exhibiting the accused to identifying witnesses before trial in the absence of counsel must be excluded at trial.
Our own Supreme Court has likewise denied retrospective application of a prophylactic rule. In Commonwealth v. Godfrey, 434 Pa. 532, 254 A.2d 923 (1969), the Court held that the rule of Boykin v. Alabama, 395 U.S. 238, 89 S.Ct. 1709, 23 L.Ed.2d 274 (1969), requiring an on-the-record colloquy to ensure a voluntary and intelligent guilty plea, is prospective only.
If the new rule in question is not an exclusionary or prophylactic rule but a rule required to ensure the integrity of the fact-finding process, retrospective application is required. The United States Supreme Court recognized this distinction in Linkletter v. Walker, supra :
Finally, in each of the three areas in which we have applied our rule retrospectively the principle we applied went to the fairness of the trial — the very integrity of the fact-finding, process. [Griffin v. Illinois, 351 U.S. 12, 76 S.Ct. 585, 100 L.Ed. 891 (1956) (due process requires that an indigent criminal defendant be furnished transcripts of his trial in order to prepare his appeal); Gideon v. Wainwright, 372 U.S. 335, 83 S.Ct. 792, 9 L.Ed.2d 799 (1963) *33(counsel must be appointed for indigents charged with felonies); and Jackson v. Denno, 378 U.S. 368, 84 S.Ct. 1774, 12 L.Ed.2d 908 (1964) (a hearing must be held before a judge to determine the voluntariness of a confession before evidence of the confession can be heard by a jury)]. Here, as we have pointed out, the fairness of the trial is not under attack. All that petitioner attacks is the admissibility of evidence, the reliability and relevancy of which is not questioned, and which may well have no effect on the outcome.
381 U.S. at 639, 85 S.Ct. at 1743.
The majority characterizes the rule announced in Wardius as prophylactic only and therefore not requiring retrospective application. Majority Opinion at 311. This ignores the reason the rule was formulated, which was that it was required to ensure “the very integrity of the fact-finding process.” This is the plain meaning of the Court’s statement, already quoted above, in explanation of the rule:
It is fundamentally unfair to require a defendant to divulge the details of his own case while at the same time subjecting him to the hazard of surprise concerning refutation of the very pieces of evidence which he disclosed to the State.
412 U.S. at 476, 93 S.Ct. at 2212.
Here, the nature of appellant’s trial was fundamentally different by virtue of Rule 312 than would otherwise have been the case. The rule permitted the Commonwealth to “insist that [appellant’s trial] be run as a ‘search for truth’ as far as defense witnesses are concerned, while maintaining ‘poker game’ secrecy for its own witnesses.” Wardius v. Oregon, supra, 412 U.S. at 475, 93 S.Ct. at 2212. Thus appellant was deprived of the opportunity to bring before the jury any evidence to impeach or otherwise discredit the Commonwealth’s witnesses — evidence he might have discovered had he known before trial who the witnesses were.
At least one federal district court has held that because the rule of Wardius is to ensure the very integrity of the fact-finding process, Wardius should be given retrospective *34application.7 In United States ex rel. Hairston v. Warden, Ill. State Penitentiary, 407 F.Supp. 524 (N.D.Ill.1976), the court also surveyed the United States Supreme Court decisions relating to retrospective application of a new rule of constitutional dimensions and concluded that Wardius “had as its major purpose the overcoming of an ‘aspect of the criminal trial that substantially impairs its truth-finding function . . . ” 407 F.Supp. at 528-29.
The conclusion that Wardius must be retrospectively applied may have a significant effect on the administration of justice, for a number of new trials may have to be held. This possibility, however, is not a sufficient reason to deny retrospective application:
Where the major purpose of new constitutional doctrine is to overcome an aspect of the criminal trial that substantially impairs its truth-finding function . . . , the new rule has been given complete retroactive effect. Neither good-faith reliance by state or federal authorities on prior constitutional law or accepted practice, nor severe impact on the administration of justice has sufficed to require prospective application in these circumstances. Williams v. United States, 401 U.S. 646, 653, 91 S.Ct. 1148, 1152, 28 L.Ed.2d 388 (1971) (footnote omitted).
The Court has recently re-affirmed this principle:
. we have never deviated from the rule stated in Ivan [v. City of New York, 407 U.S. 203, 204,92 S.Ct. 1951, 32 L.Ed.2d 659 (1973),] that “ ‘[w]here the major purpose of new constitutional doctrine is to overcome an aspect of the criminal trial that substantially impairs its truth-finding function and so raises serious questions about the *35accuracy of guilty verdicts in past trials, the new rule [is] given complete retroactive effect.’ ”
Hankerson v. North Carolina, 432 U.S. 233, 243, 97 S.Ct. 2339, 2345, 53 L.Ed.2d 306 (filed June 17, 1977) (emphasis in original).
In discussing the effect on the administration of justice of retrospective application of Wardius, the majority makes the familiar argument that such application would open the floodgates, i. e., would vacate the sentence of every defendant tried under Rule 312. I do not believe that such an alarmist position is warranted. Retrospective application of the rule of Wardius would be limited in the same way that prospective application is. A new trial is required only when the defendant was prejudiced by enforcement of Rule 312. Where enforcement represented only harmless error the judgment of sentence will not be reversed. Commonwealth v. Jackson, supra; Commonwealth v. Jones, supra. This might be the case, for example, where the Commonwealth offered no witnesses to rebut a defendant’s alibi, or where the Commonwealth’s rebuttal witnesses were the same as its witnesses in chief. In such situations the defendant might not have been prejudiced by a failure to receive reciprocal discovery, although the burden will be on the Commonwealth to prove that enforcement of Rule 312 was harmless beyond a reasonable doubt. Chapman v. California, supra.
Finally, the majority argues that as a practical matter effective pre-trial discovery of alibi rebuttal witnesses “would be impossible for the Commonwealth.” Majority Opinion at 313. Evidently our Supreme Court disagrees, for it has recently promulgated new rules of criminal procedure that require such discovery. Pa.R.Crim.P. 305(C)(1)(a) & 305(C)(1)(c).
I would reverse and remand for a new trial consistent with the new Rules.
HOFFMAN, J., joins in this opinion.. Act of Jan. 25, 1966, P.L. (1965) 1580, § 1 et seq., 19 P.S. § 1180-1 et seq. (1976 Supp.).
. Rule 312 is no longer in force. On June 29, 1973, immediately after the announcement of the decision in Wardius v. Oregon, the Pennsylvania Supreme Court suspended the rule. A few months later the Court expressly found the rule to be unconstitutional. Commonwealth v. Contakos, 455 Pa. 136, 314 A.2d 259 (1974).
The rule provided: .
(a) When a defendant intends to offer the defense of alibi at trial, he shall at any time before or after indictment but not later than five days before trial, file notice with proof of service on the attorney for the Commonwealth, specifying his intention to claim such defense and giving the place where he will claim to have been at the time of the alleged offense and the names and addresses of the witnesses he intends to call in support of such claim.
(b) Unless the interests of justice require it, on a defense of alibi a defendant may not call any witness not named in such notice, or any witness on an alibi different from that alleged in the notice.
(c) A defendant may himself testify concerning an alibi notwithstanding he has not filed notice, but if he has filed notice and testifies concerning his presence at the time of the offense at a place different from that specified in his notice, he may be cross-examined concerning such notice.
(d) No adverse inference may be drawn against a defendant, nor may any comment be made concerning his failure to call available alibi witnesses, where such witnesses have been prevented from testifying by reason of this rule, unless the defendant or his counsel shall attempt to explain such failure to the jury.
. Appellant contends that after he had identified his alibi witnesses, the Commonwealth subjected them to intensive interrogation and threats of prosecution for perjury with the result that at least one of the witnesses changed his story and testified for the Commonwealth as an anti-alibi witness. The PCHA hearing judge did not deal with this contention. The majority first ignores this deficiency in the hearing judge’s disposition, see 19 P.S. § 1180-09, and then dismisses appellant’s contention on the ground that it was rejected by the trial judge concluding that any non-compliance with Wardius was therefore harmless error. This analysis misses the point that the danger of non-reciprocity expressed in Wardius is not the possibility that a defendant’s alibi witnesses might be turned against him by the Commonwealth (although in some cases that may be a problem), but that a defendant is denied the opportunity to learn the identity of the *27witnesses the Commonwealth will use to rebut the alibi. See discussion infra.
. Ore.Rev.Stat. § 135.875 provided:
(1) If the defendant in a criminal action proposes to rely in any way on alibi evidence, he shall, not less than five days before the trial of the cause, file and serve upon the district attorney a written notice of his purpose to offer such evidence, which notice shall state specifically the place or places where the defendant claims to have been at the time or times of the alleged offense together with the name and residence or business address of each witness upon whom the defendant intends to rely for alibi evidence. If the defendant fails to file and serve such notice, he shall not be permitted to introduce alibi evidence at the trial of the cause unless the court for good cause orders otherwise.
. The majority points out that at trial appellant was permitted, over the Commonwealth’s objection, to introduce the testimony of an alibi witness whose name did not appear on appellant’s pre-trial alibi notice. To me, that fact is immaterial, for it does not affect the fact that discovery was not reciprocal. •
. Both this court and the Pennsylvania Supreme Court have applied Wardius on direct appeal in cases where the conviction was preWardius. Commonwealth v. Sweeney, 464 Pa. 425, 347 A.2d 286 (1975); Commonwealth v. Contakos, 455 Pa. 136, 314 A.2d 259 (1974); Commonwealth v. McCleary, 228 Pa.Super. 224, 323 A.2d 243 (1974); Commonwealth v. Horace, 226 Pa.Super. 531, 323 A.2d 895 (1974). For a discussion of the different situations in which the question of retrospective application of a new rule arises, see Commonwealth v. Williams, 232 Pa.Super. 339, 331 A.2d 875 (1974), allocatur denied. The question whether to apply Wardius to a *31conviction that has become final is apparently of first impression in the Commonwealth.
. Cf. Riley v. Havener, 391 F.Supp. 1177 (N.D. Ohio 1974) (on habeas corpus, Wardius applied where conviction and appeal to intermediate appellate court were pre-Wardius; dismissal of appeal to Ohio Supreme Court was after announcement of Wardius ); United States ex rel. Snyder v. Mack, 372 F.Supp. 1077 (E.D.Pa.1974) (whether Wardius should be retrospectively applied not reached; Mayer v. Moeykens, 373 F.Supp. 649 (D.Vt.1973) (Wardius not retrospectively applied where no prejudice shown).