Opinion by
Mr. Justice Roberts,Floyd Jackson was convicted of armed robbery and sentenced to one to four years imprisonment. Pursuant to rule 312 of the Pennsylvania Rules of Criminal Procedure,1 appellant notified the Commonwealth pretrial *81of the names and addresses of the witnesses he intended to call to establish an alibi. His request for the names and addresses of those witnesses the Commonwealth planned to produce to place him at the scene of the crime was refused. The Superior Court on April 12, 1973, affirmed. Commonwealth v. Jackson, 224 Pa. Superior Ct. 280, 303 A.2d 519 (1973).
On June 11, 1973, the United States Supreme Court delivered its opinion in Wardius v. Oregon, 412 U.S. 470, 93 S. Ct. 2208 (1973). There, the Supreme Court held that “the Due Process Clause of the Fourteenth Amendment forbids enforcement of alibi rules unless reciprocal discovery rights are given to criminal defendants.” Id. at 472, 93 S. Ct. at 2211. Jackson’s petition for allowance of appeal raised the question whether the failure to afford appellant reciprocal discovery violated his right to due process of law.2 We granted the petition3 and now reverse.
*82Wardius permits an accused to challenge the constitutionality of enforcement of a notice of alibi rule “by giving notice and then demanding discovery.” Id. at 477, 93 S. Ct. at 2213. Appellant provided the Commonwealth with the names and addresses of alibi witnesses he was prepared to call. Once appellant, under compulsion of rule 312, disclosed his alibi witnesses to the Commonwealth, the Commonwealth was constitutionally bound to afford appellant reciprocal discovery by furnishing him the names and addresses of any witnesses whose testimony would refute his alibi.4 The Supreme Court held in Wardius “that in the absence of a strong showing of state interests to the contrary, discovery must be a two-way street. The State may not insist that trials be run as a ‘search for truth’ so far as defense witnesses are concerned, while maintaining ‘poker game’ secrecy for its own witnesses. 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.” Id. at 475, 93 S. Ct. at 2212-13.5
Reciprocity, then, is the key to Wardius.6 Appellant in the instant case was required “to divulge the details *83of his own case.” Here, too, appellant was subjected “to the hazard of surprise.” Because appellant was not granted reciprocal discovery, even after Ms express request, the enforcement of rule 312 violated appellant’s right to due process of law. It was constitutional error to require appellant to supply the names of his alibi witnesses, without directing the Commonwealth to afford appellant reciprocal discovery rights.7
We cannot say that this error was harmless beyond a reasonable doubt. See Chapman v. California, 386 U.S. 18, 87 S. Ct. 824 (1967); Commonwealth v. Davis, 452 Pa. 171, 305 A.2d 715 (1973); Commonwealth v. Padgett, 428 Pa. 229, 237 A.2d 209 (1968). Appellant’s alibi witnesses testified that appellant was at their home at the time the robbery was committed, and that they saw no gun in his possession. Two witnesses, whose names appellant sought to discover pretrial, directly contradicted the testimony of appellant’s alibi witnesses. One identified appellant as a person who fled from the scene of the crime; the other testified *84that shortly after the robbery he saw appellant handle a revolver.
The failure of the Commonwealth to afford appellant reciprocal discovery rights made it impossible for appellant either to investigate the two witnesses whom the Commonwealth called to refute his alibi, or to explore the weaknesses in their stories. By placing appellant at the scene of the crime and by placing a pistol in his hand, the testimony of these two witnesses (whose names the Commonwealth refused to disclose) refuted appellant’s alibi. These witnesses were essential to the Commonwealth’s case; their credibility indispensable. Had appellant been afforded reciprocal discovery, he would have had the opportunity to be better prepared for cross-examination, and he may have had a better chance to impeach the Commonwealth’s witnesses.
Constitutional error was committed when appellant was required to divulge the details of his case and was not afforded reciprocal discovery rights. The Commonwealth simply has not shown that the error complained of was harmless beyond a reasonable doubt. Because Floyd Jackson’s right to due process of law was violated by the enforcement of rule 312, he, like the appellants in Wardius,8 Commonwealth v. Williams,9 Commonwealth v. Contakos10 and Commonwealth v. Diana,11 is entitled to a new trial.12
The judgment of sentence is reversed and a new trial granted.
Pa. R. Crim. P. 312 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 *81testifies 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.”
On June 29, 1973, this Court suspended rule 312. In Commonwealth v. Contakos, 455 Pa. 136, 314 A.2d 259 (1974), we held that “enforcement of the rule in the instant trial proceedings requires the grant of a new trial.” Id. at 138, 314 A.2d at 261. See also Commonwealth v. Williams, 456 Pa. 619, 317 A.2d 49 (1974); Commonwealth v. Diana, 455 Pa. 267, 314 A.2d 262 (1974).
U.S. Const. amend. XIV, § 1; Pa. Const. art. I, § 9. Our analysis of the federal constitutional claim applies equally to the state constitutional provision. See Commonwealth v. Contakos, 455 Pa. 136, 314 A.2d 259 (1974).
Appellate Court Jurisdiction Act of 1970, Act of July 31, 1970, P.L. 673, art. II, § 204(a), 17 P.S. § 211.204(a) (Supp. 1973).
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 ease in chief. See 412 U.S. at 474-76, 93 S. Ct. at 2212-13.
See Commonwealth v. Contakos, 455 Pa. 136, 138, 140, 314 A.2d 259, 261 (1974). See generally Brennan, The Criminal Prosecution: Sporting Event or Quest for Truth?, 1963 Wash. U.L.Q. 279; Goldstein, The State and the Accused: Balance of Advantage in Criminal Procedure, 69 Yale L..T. 1149 (1960); Note, The Preclusion Sanction — A Violation of the Constitutional Right to Present a Defense, 81 Yale L.J. 1342 (1972).
See 412 U.S. at 474 & n.6, 93 S. Ct. at 2212 & n.6. See also Williams v. Florida, 399 U.S. 78, 90 S. Ct. 1893 (1970). Cf. In re *83Winship, 397 U.S. 358, 361-64, 90 S. Ct. 1068, 1070-73 (1970); Brady v. Maryland, 373 U.S. 83, 83 S. Ct. 1194 (1963).
Faced with the unconstitutionality of enforcing rule 312 in this case, the trial court had several options available to it. It could have directed that the Commonwealth, at some ample time prior to trial, give appellant the names and addresses of all witnesses it would call to refute appellant’s alibi. See People v. Elliott, 75 Misc. 2d 754, 348 N.Y.S.2d 902, aff’g 74 Misc. 2d 974, 346 N.Y.S.2d 632 (Sup. Ct. Kings County 1973). Or, if the Commonwealth did not provide appellant with the names of the witnesses who would be called to refute his alibi, the trial court could have precluded the Commonwealth from introducing their testimony. See People v. Haynesworth, 75 Misc. 2d 75, 347 N.Y.S.2d 540 (Sup. Ct. Queens County 1973); see also People v. Sumpter, 75 Misc. 2d 55, 347 N.Y.S.2d 670 (Sup. Ct. New York County 1973). Cf. State v. Morales, 266 Ore. 921, 513 P.2d 798 (1973); State v. Kelsaw, 14 Or. App. 313, 513 P.2d 516, on remand from 412 U.S. 947, 93 S. Ct. 3016 (1973).
412 U.S. 470, 93 S. Ct. 2208 (1973).
456 Pa. 619, 317 A.2d 49 (1974).
455 Pa. 136, 314 A.2d 259 (1974).
455 Pa. 267, 314 A.2d 262 (1974).
Our disposition of this ease mates unnecessary consideration of appellant’s other claim that the Commonwealth suppressed material evidence favorable to him. See Brady v. Maryland, 373 U.S. 83, 83 S. Ct. 1194 (1963); Napue v. Illinois, 360 U.S. 264, 79 S. Ct. 1173 (1959).