HARRIS v. NEW YORK Certiorari to the Court of Appeals of New Y ork 401 U.S. 222(1971) MR. CHIE F JU STICE BU RG ER delivered the opinio n of the Co urt. We granted the writ in this case to consider petitioner's claim that a statem ent m ade by him to police un der circum stances rendering it inadmissible to establish the prosecution s case in chief under Miranda v. Arizona, 384 U.S, 436 (1966), may not be used to impeach his credibility. The State of New York charged petitioner in a two-count indictment with twice selling heroin to an undercover police officer. At a subsequent jury trial the officer w as the States chief witness, and he testified as to details of the two sales. A second officer verified collateral details of the sales, and a third offered testimony about the chemical analysis of the heroin. Petitioner took the stand in his own defense. He admitted knowing the undercover police officer but denied a sale on January 4, 1966. He admitted making a sale of contents of a glassine bag to the officer on Janu ary 6 but claimed it w as baking pow der and part of a scheme to defraud the purchaser. On cross-examination petitioner was asked seriatim whether he had made specified statements to the police immediately following his arrest on January 7— statements that partially contradicted petitioners direct testimony at trial. In response to the cross-examination, petitioner testified that he could not remem ber virtually any of the questions or answers recited by the prosecutor. At the request of petitioner's counsel the written statem ent from w hich the prosecutor had read questions and answ ers in his impeaching process was placed in the record for possible use on appeal; the statement was not shown to the jury. The trial jud ge instructed the jury that the statem ents attributed to petitioner by the prosecution could be considered only in passing on petitioner’s credibility and not as evidence of guilt. In closing summations both counsel argued the substance of the impeaching statem ents. The jury then foun d petitioner guilty on the seco nd coun t of the indictment. . . . At trial the prosecution made no effort in its case in chief to use the statements alleged ly made by petitioner, conceding that they were inadmissible under Miranda v. A rizona, 384 US- 436 (1 966 ). . . . Petitioner makes no claim that the statements made to the police w ere coerced or involuntary. Some com ments in the Miranda opinion can indeed be read as indicating a bar to use of an uncounseled statement for any purpose, but discussion of that issue was not at all necessary to the Courts holding and cannot be regarded as controlling . . . In Walder v. United States. 347 U.S. 62 (1954), the Court permitted physical evidence, inadmissible in the case in chief, to be used for impeachm ent purposes. It is one thing to say that the Government cannot make an affirmative u se of evidence unlawfu lly ob tained . It is quite another to say that the defendant can turn the illegal method by which ev idence in the Government's possession was obtained to his own advantage, and provide himself with a shield against contradiction of his untruths. Such an ex tension of the W eeks doctrine would be a perversion of the Fourth Am endment. [T]here is hardly Justification for lotting the defendant affirmatively resort to perjurious testimony in reliance on l:he Governments disability to challeng e his credibility. [347 U.S., at 65.j It is true that Walder was impeached as to collateral matters included in his direct exam ination, whereas petitioner here was imp eached as to testimony bearing more directly on the crimes charged. We are not persuaded that there is a difference in principle that w arrants a result different from that reached by the Court in Walder. Petitioner's testimony in his own behalf concerning the even ts of January 7 contrasted sharp ly with what he told the police shortly after his arrest. The impeachment process here undoubtedly provided valuable aid to the jury in assessing petitioner's credibility , and the benefits of this process shou ld not be lost, in our view , because of the speculative p ossibility that impermissible police conduct will be encouraged thereby. Assuming that the exclusionary rule has a deterrent effect on proscribed police conduct, sufficient deterrence flow s wh en the evid ence in question is made unavailab le to the prosecution in its case in chief. Every criminal defendant is privileged to testify in his own defense, or to refuse to do so. But that privilege cannot be construed to include the right to commit perjury. Having voluntarily taken the stand, petitioner was under an obligation to speak truthfully and accurately, and the prosecution here did no more than utilize the traditional truth-testing devices of the ad versary process. . . . The shield provided by Miranda cannot be perverted into a license to use perjury by way of a defense, free from the risk of confrontation with prior inconsistent utterances. W e hold , therefore, that petitioner's credibility was appropriately impeached by use of his earlier conflicting statements. Affirmed. [JUSTICE BLACK dissented without an opinion. The dissenting opinion of JUSTICE BRENNAN, joined by JUSTICES DOUGLAS and MARSHALL, is om itted.]