opinion: NIX, WARDEN v. WHITESIDE
  No. 84-1321.
  Argued November 5, 1985
  Decided February 26, 1986
  BURGER, C. J., delivered the opinion of the Court, in which White, Powell, Rehnquist, and O’Connor, JJ., joined. Brennan, J., filed an opinion concurring in the judgment, post, p. 176. Blackmun, J., filed an opinion concurring in the judgment, in which Brennan, Marshall, and Stevens, JJ., joined, post, p. 177. Stevens, J., filed an opinion concurring in the judgment, post, p. 190.
  Brent R. Appel, Deputy Attorney General of Iowa, argued the cause for petitioner. With him on the briefs were Thomas J. Miller, Attorney General, and Thomas D. McGrane, Assistant Attorney General.
  Patrick Reilly Grady, by appointment of the Court, 471 U. S. 1097, argued the cause and filed a brief for respondent.
  Briefs of amici curiae urging reversal were filed for the Legal Foundation of America by Jean Fleming Powers and David Crump; and for the National Association of Criminal Defense Lawyers by Michael L. Bender and Bruce M. Lyons.
  John C. Shepherd, Michael Franck, and George Kuhlman filed a brief for the American Bar Association as amicus curiae.
  Chief Justice Burger
  delivered the opinion of the Court.
  We granted certiorari to decide whether the Sixth Amendment right of a criminal defendant to assistance of counsel is violated when an attorney refuses to cooperate with the defendant in presenting perjured testimony at his trial.
  I
  A
  Whiteside was convicted of second-degree murder by a jury verdict which was affirmed by the Iowa courts. The killing took place on February 8, 1977, in Cedar Rapids, Iowa. Whiteside and two others went to one Calvin Love’s apartment late that night, seeking marihuana. Love was in bed when Whiteside and his companions arrived; an argument between Whiteside and Love over the marihuana ensued. At one point, Love directed his girlfriend to get his “piece,” and at another point got up, then returned to his bed. According to Whiteside’s testimony, Love then started to reach under his pillow and moved toward Whiteside. Whiteside stabbed Love in the chest, inflicting a fatal wound.
  Whiteside was charged with murder, and when counsel was appointed he objected to the lawyer initially appointed, claiming that he felt uncomfortable with a lawyer who had formerly been a prosecutor. Gary L. Robinson was then appointed and immediately began an investigation. Whiteside gave him a statement that he had stabbed Love as the latter “was pulling a pistol from underneath the pillow on the bed.” Upon questioning by Robinson, however, Whiteside indicated that he had not actually seen a gun, but that he was convinced that Love had a gun. No pistol was found on the premises; shortly after the police search following the stabbing, which had revealed no weapon, the victim’s family had removed all of the victim’s possessions from the apartment. Robinson interviewed Whiteside’s companions who were present during the stabbing, and none had seen a gun during the incident. Robinson advised Whiteside that the existence of a gun was not necessary to establish the claim of self-defense, and that only a reasonable belief that the victim had a gun nearby was necessary even though no gun was actually present.
  Until shortly before trial, Whiteside consistently stated to Robinson that he had not actually seen a gun, but that he was convinced that Love had a gun in his hand. About a week before trial, during preparation for direct examination, Whiteside for the first time told Robinson and his associate Donna Paulsen that he had seen something “metallic” in Love’s hand. When asked about this, Whiteside responded:
  “[I]n Howard Cook’s case there was a gun. If I don’t say I saw a gun, I’m dead.”
  Robinson told Whiteside that such testimony would be perjury and repeated that it was not necessary to prove that a gun was available but only that Whiteside reasonably believed that he was in danger. On Whiteside’s insisting that he would testify that he saw “something metallic” Robinson told him, according to Robinson’s testimony:
  “[W]e could not allow him to [testify falsely] because that would be perjury, and as officers of the court we would be suborning perjury if we allowed him to do it; ... I advised him that if he did do that it would be my duty to advise the Court of what he was doing and that I felt he was committing perjury; also, that I probably would be allowed to attempt to impeach that particular testimony.” App. to Pet. for Cert. A-85.
  Robinson also indicated he would seek to withdraw from the representation if Whiteside insisted on committing perjury.
  Whiteside testified in his own defense at trial and stated that he “knew” that Love had a gun and that he believed Love was reaching for a gun and he had acted swiftly in self-defense. On cross-examination, he admitted that he had not actually seen a gun in Love’s hand. Robinson presented evidence that Love had been seen with a sawed-off shotgun on other occasions, that the police search of the apartment may have been careless, and that the victim’s family had removed everything from the apartment shortly after the crime. Robinson presented this evidence to show a basis for White-side’s asserted fear that Love had a gun.
  The jury returned a verdict of second-degree murder, and Whiteside moved for a new trial, claiming that he had been deprived of a fair trial by Robinson’s admonitions not to state that he saw a gun or “something metallic.” The trial court held a hearing, heard testimony by Whiteside and Robinson, and denied the motion. The trial court made specific findings that the facts were as related by Robinson.
  The Supreme Court of Iowa affirmed respondent’s conviction. State v. Whiteside, 272 N. W. 2d 468 (1978). That court held that the right to have counsel present all appropriate defenses does not extend to using perjury, and that an attorney’s duty to a client does not extend to assisting a client in committing perjury. Relying on DR 7-102(A)(4) of the Iowa Code of Professional Responsibility for Lawyers, which expressly prohibits an attorney from using perjured testimony, and Iowa Code § 721.2 (now Iowa Code § 720.3 (1986)), which criminalizes subornation of perjury, the Iowa court concluded that not only were Robinson’s actions permissible, but were required. The court commended “both Mr. Robinson and Ms. Paulsen for the high ethical manner in which this matter was handled.”
  B
  Whiteside then petitioned for a writ of habeas corpus in the United States District Court for the Southern District of Iowa. In that petition Whiteside alleged that he had been denied effective assistance of counsel and of his right to present a defense by Robinson’s refusal to allow him to testify as he had proposed. The District Court denied the writ. Accepting the state trial court’s factual finding that Whiteside’s intended testimony would have been perjurious, it concluded that there could be no grounds for habeas relief since there is no constitutional right to present a perjured defense.
  The United States Court of Appeals for the Eighth Circuit reversed and directed that the writ of habeas corpus be granted. Whiteside v. Scurr, 744 F. 2d 1323 (1984). The Court of Appeals accepted the findings of the trial judge, affirmed by the Iowa Supreme Court, that trial counsel believed with good cause that Whiteside would testify falsely and acknowledged that under Harris v. New York, 401 U. S. 222 (1971), a criminal defendant’s privilege to testify in his own behalf does not include a right to commit perjury. Nevertheless, the court reasoned that an intent to commit perjury, communicated to counsel, does not alter a defendant’s right to effective assistance of counsel and that Robinson’s admonition to Whiteside that he would inform the court of Whiteside’s perjury constituted a threat to violate the attorney’s duty to preserve client confidences. According to the Court of Appeals, this threatened violation of client confidences breached the standards of effective representation set down in Strickland v. Washington, 466 U. S. 668 (1984). The court also concluded that Strickland’s prejudice requirement was satisfied by an implication of prejudice from the conflict between Robinson’s duty of loyalty to his client and his ethical duties. A petition for rehearing en banc was denied, with Judges Gibson, Ross, Fagg, and Bowman dissenting. Whiteside v. Scurr, 750 F. 2d 713 (1984). We granted certiorari, 471 U. S. 1014 (1985), and we reverse.
  I — I » — I
  A
  The right of an accused to testify in his defense is of relatively recent origin. Until the latter part of the preceding century, criminal defendants in this country, as at common law, were considered to be disqualified from giving sworn testimony at their own trial by reason of their interest as a party to the case. See, e. g., Ferguson v. Georgia, 365 U. S. 570 (1961); R. Morris, Studies in the History of American Law 59-60 (2d ed. 1959). Iowa was among the states that adhered to this rule of disqualification. State v. Laffer, 38 Iowa 422 (1874).
  By the end of the 19th century, however, the disqualification was finally abolished by statute in most states and in the federal courts. Act of Mar. 16, 1878, ch. 37, 20 Stat. 30-31; see Thayer, A Chapter of Legal History in Massachusetts, 9 Harv. L. Rev. 1, 12 (1895). Although this Court has never explicitly held that a criminal defendant has a due process right to testify in his own behalf, cases in several Circuits have so held, and the right has long been assumed. See, e. g., United States v. Curtis, 742 F. 2d. 1070, 1076 (CA7 1984); United States v. Bifield, 702 F. 2d 342, 349 (CA2), cert. denied, 461 U. S. 931 (1983). We have also suggested that such a right exists as a corollary to the Fifth Amendment privilege against compelled testimony, see Harris v. New York, supra, at 225. See also Ferguson, 365 U. S., at 598-601 (concurring opinion of Frankfurter, J.); id., at 601-603 (concurring opinion of Clark, J.).
  B
  In Strickland v. Washington, we held that to obtain relief by way of federal habeas corpus on a claim of a deprivation of effective assistance of counsel under the Sixth Amendment, the movant must establish both serious attorney error and prejudice. To show such error, it must be established that the assistance rendered by counsel was constitutionally deficient in that “counsel made errors so serious that counsel was not functioning as ‘counsel’ guaranteed the defendant by the Sixth Amendment.” Strickland, 466 U. S., at 687. To show prejudice, it must be established that the claimed lapses in counsel’s performance rendered the trial unfair so as to “undermine confidence in the outcome” of the trial. Id., at 694.
  In Strickland, we acknowledged that the Sixth Amendment does not require any particular response by counsel to a problem that may arise. Rather, the Sixth Amendment inquiry is into whether the attorney’s conduct was “reasonably effective.” To counteract the natural tendency to fault an unsuccessful defense, a court reviewing a claim of ineffective assistance must “indulge a strong presumption that counsel’s conduct falls within the wide range of reasonable professional assistance.” Id., at 689. In giving shape to the perimeters of this range of reasonable professional assistance, Strickland mandates that
  “[prevailing norms of practice as reflected in American Bar Association Standards and the like, . . . are guides to determining what is reasonable, but they are only guides.” Id., at 688.
  Under the Strickland standard, breach of an ethical standard does not necessarily make out a denial of the Sixth Amendment guarantee of assistance of counsel. When examining attorney conduct, a court must be careful not to narrow the wide range of conduct acceptable under the Sixth Amendment so restrictively as to constitutionalize particular standards of professional conduct and thereby intrude into the state’s proper authority to define and apply the standards of professional conduct applicable to those it admits to practice in its courts. In some future case challenging attorney conduct in the course of a state-court trial, we may need to define with greater precision the weight to be given to recognized canons of ethics, the standards established by the state in statutes or professional codes, and the Sixth Amendment, in defining the proper scope and limits on that conduct. Here we need not face that question, since virtually all of the sources speak with one voice.
  C
  We turn next to the question presented: the definition of the range of “reasonable professional” responses to a criminal defendant client who informs counsel that he will perjure himself on the stand. We must determine whether, in this setting, Robinson’s conduct fell within the wide range of professional responses to threatened client perjury acceptable under the Sixth Amendment.
  In Strickland, we recognized counsel’s duty of loyalty and his “overarching duty to advocate the defendant’s cause.” Ibid. Plainly, that duty is limited to legitimate, lawful conduct compatible with the very nature of a trial as a search for truth. Although counsel must take all reasonable lawful means to attain the objectives of the client, counsel is precluded from taking steps or in any way assisting the client in presenting false evidence or otherwise violating the law. This principle has consistently been recognized in most unequivocal terms by expositors of the norms of professional conduct since the first Canons of Professional Ethics were adopted by the American Bar Association in 1908. The 1908 Canon 32 provided:
  “No client, corporate or individual, however powerful, nor any cause, civil or political, however important, is entitled to receive nor should any lawyer render any service or advice involving disloyalty to the law whose ministers we are, or disrespect of the judicial office, which we are bound to uphold, or corruption of any person or persons exercising a public office or private trust, or deception or betrayal of the public. ... He must. . . observe and advise his client to observe the statute law . . . .”
  Of course, this Canon did no more than articulate centuries of accepted standards of conduct. Similarly, Canon 37, adopted in 1928, explicitly acknowledges as an exception to the attorney’s duty of confidentiality a client’s announced intention to commit a crime:
  “The announced intention of a client to commit a crime is not included within the confidences which [the attorney] is bound to respect.”
  These principles have been carried through to contemporary codifications of an attorney’s professional responsibility. Disciplinary Rule 7-102 of the Model Code of Professional Responsibility (1980), entitled “Representing a Client Within the Bounds of the Law,” provides:
  “(A) In his representation of a client, a lawyer shall not:
  “(4) Knowingly use perjured testimony or false evidence.
  “(7) Counsel or assist his client in conduct that the lawyer knows to be illegal or fraudulent.”
  This provision has been adopted by Iowa, and is binding on all lawyers who appear in its courts. See Iowa Code of Professional Responsibility for Lawyers (1985). The more recent Model Rules of Professional Conduct (1983) similarly admonish attorneys to obey all laws in the course of representing a client:
  “RULE 1.2 Scope of Representation
  “(d) A lawyer shall not counsel a client to engage, or assist a client, in conduct that the lawyer knows is criminal or fraudulent. . . .”
  Both the Model Code of Professional Responsibility and the Model Rules of Professional Conduct also adopt the specific exception from the attorney-client privilege for disclosure of perjury that his client intends to commit or has committed. DR 4-101(C)(3) (intention of client to commit a crime); Rule 3.3 (lawyer has duty to disclose falsity of evidence even if disclosure compromises client confidences). Indeed, both the Model Code and the Model Rules do not merely authorize disclosure by counsel of client perjury; they require such disclosure. See Rule 3.3(a)(4); DR 7-102(B)(l); Committee on Professional Ethics and Conduct of Iowa State Bar Assn. v. Crary, 245 N. W. 2d 298 (Iowa 1976).
  These standards confirm that the legal profession has accepted that an attorney’s ethical duty to advance the interests of his client is limited by an equally solemn duty to comply with the law and standards of professional conduct; it specifically ensures that the client may not use false evidence. This special duty of an attorney to prevent and disclose frauds upon the court derives from the recognition that perjury is as much a crime as tampering with witnesses or jurors by way of promises and threats, and undermines the administration of justice. See 1 W. Burdick, Law of Crime §§293, 300, 318-336 (1946).
  The offense of perjury was a crime recognized at common law, id., at p. 475, and has been made a felony in most states by statute, including Iowa. Iowa Code § 720.2 (1985). See generally 4 C. Torcia, Wharton’s Criminal Law §631 (14th ed. 1981). An attorney who aids false testimony by questioning a witness when perjurious responses can be anticipated risks prosecution for subornation of perjury under Iowa Code §720.3 (1985).
  It is universally agreed that at a minimum the attorney’s first duty when confronted with a proposal for perjurious testimony is to attempt to dissuade the client from the unlawful course of conduct. Model Rules of Professional Conduct, Rule 3.3, Comment; Wolfram, Client Perjury, 50 S. Cal. L. Rev. 809, 846 (1977). A statement directly in point is found in the commentary to the Model Rules of Professional Conduct under the heading “False Evidence”:
  ‘When false evidence is offered by the client, however, a conflict may arise between the lawyer’s duty to keep the client’s revelations confidential and the duty of candor to the court. Upon ascertaining that material evidence is false, the lawyer should seek to persuade the client that the evidence should not be offered or, if it has been offered, that its false character should immediately be disclosed.” Model Rules of Professional Conduct, Rule 3.3, Comment (1983) (emphasis added).
  The commentary thus also suggests that an attorney’s revelation of his client’s perjury to the court is a professionally responsible and acceptable response to the conduct of a client who has actually given perjured testimony. Similarly, the Model Rules and the commentary, as well as the Code of Professional Responsibility adopted in Iowa, expressly permit withdrawal from representation as an appropriate response of an attorney when the client threatens to commit perjury. Model Rules of Professional Conduct, Rule 1.16(a)(1), Rule 1.6, Comment (1983); Code of Professional Responsibility, DR 2-110(B), (C) (1980). Withdrawal of counsel when this situation arises at trial gives rise to many difficult questions including possible mistrial and claims of double jeopardy.
  The essence of the brief amicus of the American Bar Association reviewing practices long accepted by ethical lawyers is that under no circumstance may a lawyer either advocate or passively tolerate a client’s giving false testimony. This, of course, is consistent with the governance of trial conduct in what we have long called “a search for truth.” The suggestion sometimes made that “a lawyer must believe his client, not judge him” in no sense means a lawyer can honorably be a party to or in any way give aid to presenting known perjury.
  D
  Considering Robinson’s representation of respondent in light of these accepted norms of professional conduct, we discern no failure to adhere to reasonable professional standards that would in any sense make out a deprivation of the Sixth Amendment right to counsel. Whether Robinson’s conduct is seen as a successful attempt to dissuade his client from committing the crime of perjury, or whether seen as a “threat” to withdraw from representation and disclose the illegal scheme, Robinson’s representation of Whiteside falls well within accepted standards of professional conduct and the range of reasonable professional conduct acceptable under Strickland.
  The Court of Appeals assumed for the purpose of the decision that Whiteside would have given false testimony had counsel not intervened; its opinion denying a rehearing en banc states:
  “[W]e presume that appellant would have testified falsely.
  “. . . Counsel’s actions prevented [Whiteside] from testifying falsely. We hold that counsel’s action deprived appellant of due process and effective assistance of counsel.
  “Counsel’s actions also impermissibly compromised appellant’s right to testify in his own defense by conditioning continued representation by counsel and confidentiality upon appellant’s restricted testimony.” 750 F. 2d., at 714-715.
  While purporting to follow Iowa’s highest court “on all questions of state law,” 744 F. 2d., at 1330, the Court of Appeals reached its conclusions on the basis of federal constitutional due process and right to counsel.
  The Court of Appeals’ holding that Robinson’s “action deprived [Whiteside] of due process and effective assistance of counsel” is not supported by the record since Robinson’s action, at most, deprived Whiteside of his contemplated perjury. Nothing counsel did in any way undermined Whiteside’s claim that he believed the victim was reaching for a gun. Similarly, the record gives no support for holding that Robinson’s action “also impermissibly compromised [Whiteside’s] right to testify in his own defense by conditioning continued representation . . . and confidentiality upon [Whiteside’s] restricted testimony.” The record in fact shows the contrary: (a) that Whiteside did testify, and (b) he was “restricted” or restrained only from testifying falsely and was aided by Robinson in developing the basis for the fear that Love was reaching for a gun. Robinson divulged no client communications until he was compelled to do so in response to Whiteside’s post-trial challenge to the quality of his performance. We see this as a case in which the attorney successfully dissuaded the client from committing the crime of perjury.
  Paradoxically, even while accepting the conclusion of the Iowa trial court that Whiteside’s proposed testimony would have been a criminal act, the Court of Appeals held that Robinson’s efforts to persuade Whiteside not to commit that crime were improper, first, as forcing an impermissible choice between the right to counsel and the right to testify; and, second, as compromising client confidences because of Robinson’s threat to disclose the contemplated perjury.
  Whatever the scope of a constitutional right to testify, it is elementary that such a right does not extend to testifying falsely. In Harris v. New York, we assumed the right of an accused to testify “in his own defense, or to refuse to do so” and went on to hold:
  “[T]hat privilege cannot be construed to include the right to commit perjury. See United States v. Knox, 396 U. S. 77 (1969); cf. Dennis v. United States, 384 U. S. 855 (1966). Having voluntarily taken the stand, petitioner was under an obligation to speak truthfully . . . .” 401 U. S., at 225.
  In Harris we held the defendant could be impeached by prior contrary statements which had been ruled inadmissible under Miranda v. Arizona, 384 U. S. 436 (1966). Harris and other cases make it crystal clear that there is no right whatever— constitutional or otherwise — for a defendant to use false evidence. See also United States v. Havens, 446 U. S. 620, 626-627 (1980).
  The paucity of authority on the subject of any such “right” may be explained by the fact that such a notion has never been responsibly advanced; the right to counsel includes no right to have a lawyer who will cooperate with planned perjury. A lawyer who would so cooperate would be at risk of prosecution for suborning perjury, and disciplinary proceedings, including suspension or disbarment.
  Robinson’s admonitions to his client can in no sense be said to have forced respondent into an impermissible choice between his right to counsel and his right to testify as he proposed for there was no permissible choice to testify falsely. For defense counsel to take steps to persuade a criminal defendant to testify truthfully, or to withdraw, deprives the defendant of neither his right to counsel nor the right to testify truthfully. In United States v. Havens, supra, we made clear that “when defendants testify, they must testify truthfully or suffer the consequences.” Id., at 626. When an accused proposes to resort to perjury or to produce false evidence, one consequence is the risk of withdrawal of counsel.
  On this record, the accused enjoyed continued representation within the bounds of reasonable professional conduct and did in fact exercise his right to testify; at most he was denied the right to have the assistance of counsel in the presentation of false testimony. Similarly, we can discern no breach of professional duty in Robinson's admonition to respondent that he would disclose respondent’s perjury to the court. The crime of perjury in this setting is indistinguishable in substance from the crime of threatening or tampering with a witness or a juror. A defendant who informed his counsel that he was arranging to bribe or threaten witnesses or members of the jury would have no “right” to insist on counsel’s assistance or silence. Counsel would not be limited to advising against that conduct. An attorney’s duty of confidentiality, which totally covers the client’s admission of guilt, does not extend to a client’s announced plans to engage in future criminal conduct. See Clark v. United States, 289 U. S. 1, 15 (1933). In short, the responsibility of an ethical lawyer, as an officer of the court and a key component of a system of justice, dedicated to a search for truth, is essentially the same whether the client announces an intention to bribe or threaten witnesses or jurors or to commit or procure perjury. No system of justice worthy of the name can tolerate a lesser standard.
  The rule adopted by the Court of Appeals, which seemingly would require an attorney to remain silent while his client committed perjury, is wholly incompatible with the established standards of ethical conduct and the laws of Iowa and contrary to professional standards promulgated by that State. The position advocated by petitioner, on the contrary, is wholly consistent with the Iowa standards of professional conduct and law, with the overwhelming majority of courts, and with codes of professional ethics. Since there has been no breach of any recognized professional duty, it follows that there can be no deprivation of the right to assistance of counsel under the Strickland standard.
  E
  We hold that, as a matter of law, counsel’s conduct complained of here cannot establish the prejudice required for relief under the second strand of the Strickland inquiry. Although a defendant need not establish that the attorney’s deficient performance more likely than not altered the outcome in order to establish prejudice under Strickland, a defendant must show that “there is a reasonable probability that, but for counsel’s unprofessional errors, the result of the proceeding would have been different.” 466 U. S., at 694. According to Strickland, “[a] reasonable probability is a probability sufficient to undermine confidence in the outcome.” Ibid. The Strickland Court noted that the “benchmark” of an ineffective-assistance claim is the fairness of the adversary proceeding, and that in judging prejudice and the likelihood of a different outcome, “[a] defendant has no entitlement to the luck of a lawless decisionmaker.” Id., at 695.
  Whether he was persuaded or compelled to desist from perjury, Whiteside has no valid claim that confidence in the result of his trial has been diminished by his desisting from the contemplated perjury. Even if we were to assume that the jury might have believed his perjury, it does not follow that Whiteside was prejudiced.
  In his attempt to evade the prejudice requirement of Strickland, Whiteside relies on cases involving conflicting loyalties of counsel. In Cuyler v. Sullivan, 446 U. S. 335 (1980), we held that a defendant could obtain relief without pointing to a specific prejudicial default on the part of his counsel, provided it is established that the attorney was “actively represent[ing] conflicting interests.” Id., at 350.
  Here, there was indeed a “conflict,” but of a quite different kind; it was one imposed on the attorney by the client’s proposal to commit the crime of fabricating testimony without which, as he put it, “I’m dead.” This is not remotely the kind of conflict of interests dealt with in Cuyler v. Sullivan. Even in that case we did not suggest that all multiple representations necessarily resulted in an active conflict rendering the representation constitutionally infirm. If a “conflict” between a client’s proposal and counsel’s ethical obligation gives rise to a presumption that counsel’s assistance was prejudi-cially ineffective, every guilty criminal’s conviction would be suspect if the defendant had sought to obtain an acquittal by illegal means. Can anyone doubt what practices and problems would be spawned by such a rule and what volumes of litigation it would generate?
  Whiteside’s attorney treated Whiteside’s proposed perjury in accord with professional standards, and since Whiteside’s truthful testimony could not have prejudiced the result of his trial, the Court of Appeals was in error to direct the issuance of a writ of habeas corpus and must be reversed.
  Reversed.
  Although courts universally condemn an attorney’s assisting in presenting perjury, Courts of Appeals have taken varying approaches on how to deal with a client’s insistence on presenting perjured testimony. The Seventh Circuit, for example, has held that an attorney’s refusal to call the defendant as a "witness did not render the conviction constitutionally infirm where the refusal to call the defendant was based on the attorney’s belief that the defendant would commit perjury. United States v. Curtis, 742 F. 2d 1070 (1984). The Third Circuit found a violation of the Sixth Amendment where the attorney could not state any basis for her belief that defendant’s proposed alibi testimony was perjured. United States ex rel. Wilcox v. Johnson, 555 F. 2d 115 (1977). See also Lowery v. Cardwell, 575 F. 2d 727 (CA9 1978) (withdrawal request in the middle of a bench trial, immediately following defendant’s testimony).
  Whiteside’s version of the events at this pretrial meeting is considerably more cryptic:
  “Q. And as you went over the questions, did the two of you come into conflict with regard to whether or not there was a weapon?
  “A. I couldn’t — I couldn’t say a conflict. But I got the impression at one time that maybe if I didn’t go along with — with what was happening, that it was no gun being involved, maybe that he will pull out of my trial.” App. to Pet. for Cert. A-70.
  The Court of Appeals agreed with the District Court’s finding that respondent properly exhausted his claims in state court. Although respondent had pressed his claim before the Supreme Court of Iowa as a denial of his due process right to a fair trial, and not as a denial of his Sixth Amendment right to counsel, the Court of Appeals accepted the District Court’s conclusion that the Sixth Amendment claim was exhausted, since further proceedings would be futile.
  There currently exist two different codifications of uniform standards of professional conduct. The Model Code of Professional Responsibility was originally adopted by the American Bar Association in 1969, and was subsequently adopted (in many cases with modification) by nearly every state. The more recent Model Rules of Professional Conduct were adopted by the American Bar Association in 1983. Since their promulgation by the American Bar Association, the Model Rules have been adopted by 11 States: Arizona, Arkansas, Delaware, Minnesota, Missouri, Montana, Nevada, New Hampshire, New Jersey, North Carolina, and Washington. See 1 ABA/BNA Lawyers’ Manual on Professional Conduct 334 (1984-1985) (New Jersey); id., at 445 (Arizona); id., at 855 (Montana, Minnesota); id., at 924 (Missouri); id., at 961 (Delaware, Washington); id., at 1026 (North Carolina); id., at 1127 (Arkansas); 2 id., at 14 (1986) (New Hampshire, Nevada). Iowa is one of the States that adopted a form of the Model Code of Professional Responsibility, but has yet to adopt the Model Rules. See Iowa Code of Professional Responsibility for Lawyers (1985).
  The brief of amicus American Bar Association, which supports petitioner, makes this point, referring to the history of codes of professional conduct which it has promulgated. The preamble to the most current version of the ethical standards recognizes the difficult choices that may confront an attorney who is sensitive to his concurrent duties to his client and to the legal system:
  “Within the framework of these Rules many difficult issues of professional discretion can arise. Such issues must be resolved through the exercise of sensitive professional and moral judgment guided by the basic principles underlying the Rules.” Preamble, Model Rules of Professional Conduct, p. 10 (1983).
  In the evolution of the contemporary standards promulgated by the American Bar Association, an early draft reflects a compromise suggesting that when the disclosure of intended perjury is made during the course of trial, when withdrawal of counsel would raise difficult questions of a mistrial holding, counsel had the option to let the defendant take the stand but decline to affirmatively assist the presentation of perjury by traditional direct examination. Instead, counsel would stand mute while the defendant undertook to present the false version in narrative form in his own words unaided by any direct examination. This conduct was thought to be a signal at least to the presiding judge that the attorney considered the testimony to be false and was seeking to disassociate himself from that course. Additionally, counsel would not be permitted to discuss the known false testimony in closing arguments. See ABA Standards for Criminal Justice, Proposed Standard 4-7.7 (2d ed. 1980). Most courts treating the subject rejected this approach and insisted on a more rigorous standard, see, e. g., United States v. Curtis, 742 F. 2d 1070 (CA7 1984); McKissick v. United States, 379 F. 2d 754 (CA5 1967); Dodd v. Florida Bar, 118 So. 2d 17, 19 (Fla.1960). The Eighth Circuit in this case and the Ninth Circuit have expressed approval of the “free narrative” standards. Whiteside v. Scurr, 744 F. 2d 1323, 1331 (CA8 1984); Lowery v. Cardwell, 575 F. 2d 727 (CA9 1978).
  The Rule finally promulgated in the current Model Rules of Professional Conduct rejects any participation or passive role whatever by counsel in allowing perjury to be presented without challenge.
  The Court of Appeals also determined that Robinson’s efforts to persuade Whiteside to testify truthfully constituted an impermissible threat to testify against his own client. We find no support for a threat to testify against Whiteside while he was acting as counsel. The record reflects testimony by Robinson that he had admonished Whiteside that if he withdrew he “probably would be allowed to attempt to impeach that particular testimony,” if Whiteside testified falsely. The trial court accepted this version of the conversation as true.
  See United States v. Curtis, 742 F. 2d 1070 (CA7 1984); Committee on Professional Ethics v. Crary, 245 N. W. 2d 298 (Iowa 1976); State v. Robinson, 290 N. C. 56, 224 S. E. 2d 174 (1976); Thornton v. United States, 357 A. 2d 429 (D. C. 1976); State v. Henderson, 205 Kan. 231, 468 P. 2d 136 (1970); McKissick v. United States, 379 F. 2d 754 (CA5 1967); In re King, 7 Utah 2d 258, 322 P. 2d 1095 (1958); In re Carroll, 244 S. W. 2d 474 (Ky. 1951); Hinds v. State Bar, 19 Cal. 2d 87, 119 P. 2d 134 (1941). Contra, Whiteside v. Scurr, 744 F. 2d 1323 (CA8 1984) (case below); Lowery v. Cardwell, 575 F. 2d 727 (CA9 1978).