JUSTICE O'CONNOR delivered the opinion of the Court.
Petitioner, Kevin Wiggins, argues that his attorneys' failure to investigate his background and present mitigating evidence of his unfortunate life history at his capital sentencing proceedings violated his Sixth Amendment right to counsel. In this case, we consider whether the United States Court of Appeals for the Fourth Circuit erred in upholding the Maryland Court of Appeals' rejection of this claim.
I
A
On September 17, 1988, police discovered 77-year-old Florence Lacs drowned in the bathtub of her ransacked apartment in Woodlawn, Maryland. Wiggins v. State, 352 Md. 580, 585, 724 A. 2d 1, 5 (1999). The State indicted petitioner for the crime on October 20, 1988, and later filed a notice of intention to seek the death penalty. Two Baltimore County public defenders, Carl Schlaich and Michelle Nethercott, assumed responsibility for Wiggins' case. In July 1989, petitioner elected to be tried before a judge in Baltimore County
stein and Amy Howe; and for Janet F. Reno et al. by Robert S. Litt, Kathleen A. Behan, and John A. Freedman.
Briefs of amici curiae urging affirmance were filed for the State of California et al. by Bill Lockyer, Attorney General of California, Manuel M. Medeiros, State Solicitor General, Robert R. Anderson, Chief Assistant Attorney General, Pamela C. Hamanaka, Senior Assistant Attorney General, and Kristofer Jorstad, A. Scott Hayward, and Donald E. De Nicola, Deputy Attorneys General, and by the Attorneys General for their respective States as follows: William H. Pryor, Jr., of Alabama, Terry Goddard of Arizona, Ken Salazar of Colorado, Thurbert E. Baker of Georgia, Lisa Madigan of Illinois, Steve Carter of Indiana, Richard P. Ieyoub of Louisiana, Mike McGrath of Montana, Jon Bruning of Nebraska, Brian Sandoval of Nevada, Jim Petro of Ohio, W A. Drew Edmondson of Oklahoma, D. Michael Fisher of Pennsylvania, Larry Long of South Dakota, Mark L. Shurtleff of Utah, Jerry W Kilgore of Virginia, and Christine O. Gregoire of Washington; and for the Criminal Justice Legal Foundation by Kent S. Scheidegger. Circuit Court. Ibid. On August 4, after a 4-day trial, the court found petitioner guilty of first-degree murder, robbery, and two counts of theft. App. 32.
After his conviction, Wiggins elected to be sentenced by a jury, and the trial court scheduled the proceedings to begin on October 11, 1989. On September 11, counsel filed a motion for bifurcation of sentencing in hopes of presenting Wiggins' case in two phases. Id., at 34. Counsel intended first to prove that Wiggins did not act as a "principal in the first degree," ibid.-i. e., that he did not kill the victim by his own hand. See Md. Ann. Code, Art. 27, § 413 (1996) (requiring proof of direct responsibility for death eligibility). Counsel then intended, if necessary, to present a mitigation case. In the memorandum in support of their motion, counsel argued that bifurcation would enable them to present each case in its best light; separating the two cases would prevent the introduction of mitigating evidence from diluting their claim that Wiggins was not directly responsible for the murder. App. 36-42, 37.
On October 12, the court denied the bifurcation motion, and sentencing proceedings commenced immediately thereafter. In her opening statement, N ethercott told the jurors they would hear evidence suggesting that someone other than Wiggins actually killed Lacs. Id., at 70-71. Counsel then explained that the judge would instruct them to weigh Wiggins' clean record as a factor against a death sentence. She concluded: "'You're going to hear that Kevin Wiggins has had a difficult life. It has not been easy for him. But he's worked. He's tried to be a productive citizen, and he's reached the age of 27 with no convictions for prior crimes of violence and no convictions, period…. I think that's an important thing for you to consider.'" Id., at 72. During the proceedings themselves, however, counsel introduced no evidence of Wiggins' life history.
Before closing arguments, Schlaich made a proffer to the court, outside the presence of the jury, to preserve bifurca tion as an issue for appeal. He detailed the mitigation case counsel would have presented had the court granted their bifurcation motion. He explained that they would have introduced psychological reports and expert testimony demonstrating Wiggins' limited intellectual capacities and childlike emotional state on the one hand, and the absence of aggressive patterns in his behavior, his capacity for empathy, and his desire to function in the world on the other. See id., at 349-351. At no point did Schlaich proffer any evidence of petitioner's life history or family background. On October 18, the court instructed the jury on the sentencing task before it, and later that afternoon, the jury returned with a sentence of death. Id., at 409-410. A divided Maryland Court of Appeals affirmed. Wiggins v. State, 324 Md. 551, 597 A. 2d 1359 (1991), cert. denied, 503 U. S. 1007 (1992).
B
In 1993, Wiggins sought postconviction relief in Baltimore County Circuit Court. With new counsel, he challenged the adequacy of his representation at sentencing, arguing that his attorneys had rendered constitutionally defective assistance by failing to investigate and present mitigating evidence of his dysfunctional background. App. to Pet. for Cert. 132a. To support his claim, petitioner presented testimony by Hans Selvog, a licensed social worker certified as an expert by the court. App. 419. Selvog testified concerning an elaborate social history report he had prepared containing evidence of the severe physical and sexual abuse petitioner suffered at the hands of his mother and while in the care of a series of foster parents. Relying on state social services, medical, and school records, as well as interviews with petitioner and numerous family members, Selvog chronicled petitioner's bleak life history. App. to Pet. for Cert. 163a.
According to Selvog's report, petitioner's mother, a chronic alcoholic, frequently left Wiggins and his siblings home alone for days, forcing them to beg for food and to eat paint chips and garbage. Id., at 166a-167a. Mrs. Wiggins' abusive behavior included beating the children for breaking into the kitchen, which she often kept locked. She had sex with men while her children slept in the same bed and, on one occasion, forced petitioner's hand against a hot stove burner-an incident that led to petitioner's hospitalization. Id., at 167a171a. At the age of six, the State placed Wiggins in foster care. Petitioner's first and second foster mothers abused him physically, id., at 175a-176a, and, as petitioner explained to Selvog, the father in his second foster home repeatedly molested and raped him. Id., at 176a-179a. At age 16, petitioner ran away from his foster home and began living on the streets. He returned intermittently to additional foster homes, including one in which the foster mother's sons allegedly gang-raped him on more than one occasion. Id., at 190a. After leaving the foster care system, Wiggins entered a Job Corps program and was allegedly sexually abused by his supervisor. Id., at 192a.
During the postconviction proceedings, Schlaich testified that he did not remember retaining a forensic social worker to prepare a social history, even though the State made funds available for that purpose. App. 487-488. He explained that he and Nethercott, well in advance of trial, decided to focus their efforts on "'retry[ing] the factual case'" and disputing Wiggins' direct responsibility for the murder. Id., at 485-486. In April 1994, at the close of the proceedings, the judge observed from the bench that he could not remember a capital case in which counsel had not compiled a social history of the defendant, explaining, "'[n]ot to do a social history, at least to see what you have got, to me is absolute error. I just-I would be flabbergasted if the Court of Appeals said anything else.'" Id., at 605. In October 1997, however, the trial court denied Wiggins' petition for postconviction relief. The court concluded that "when the decision not to investigate… is a matter of trial tactics, there is no ineffective assistance of counsel." App. to Pet. for Cert. 155a-156a.
The Maryland Court of Appeals affirmed the denial of relief, concluding that trial counsel had made "a deliberate, tactical decision to concentrate their effort at convincing the jury" that appellant was not directly responsible for the murder. Wiggins v. State, 352 Md., at 608, 724 A. 2d, at 15. The court observed that counsel knew of Wiggins' unfortunate childhood. They had available to them both the presentence investigation (PSI) report prepared by the Division of Parole and Probation, as required by Maryland law, Md. Ann. Code, Art. 41, § 4-609(d) (1988), as well as "more detailed social service records that recorded incidences of physical and sexual abuse, an alcoholic mother, placements in foster care, and borderline retardation." 352 Md., at 608-609, 724 A. 2d, at 15. The court acknowledged that this evidence was neither as detailed nor as graphic as the history elaborated in the Selvog report but emphasized that "counsel did investigate and were aware of appellant's background." Id., at 610,724 A. 2d, at 16 (emphasis in original). Counsel knew that at least one uncontested mitigating factor-Wiggins' lack of prior convictions-would be before the jury should their attempt to disprove Wiggins' direct responsibility for the murder fail. As a result, the court concluded, Schlaich and Nethercott "made a reasoned choice to proceed with what they thought was their best defense." Id., at 611-612, 724 A. 2d, at 17.
C
In September 2001, Wiggins filed a petition for writ of habeas corpus in Federal District Court. The trial court granted him relief, holding that the Maryland courts' rejection of his ineffective assistance claim "involved an unreasonable application of clearly established federal law." Wiggins v. Corcoran, 164 F. Supp. 2d 538, 557 (2001) (citing Williams v. Taylor, 529 U. S. 362 (2000)). The court rejected the State's defense of counsel's "tactical" decision to "'retry guilt,'" concluding that for a strategic decision to be reasonable, it must be "based upon information the attorney has made after conducting a reasonable investigation." 164 F. Supp. 2d, at 558. The court found that though counsel were aware of some aspects of Wiggins' background, that knowledge did not excuse them from their duty to make a "fully informed and deliberate decision" about whether to present a mitigation case. In fact, the court concluded, their knowledge triggered an obligation to look further. Id., at 559.
Reviewing the District Court's decision de novo, the Fourth Circuit reversed, holding that counsel had made a reasonable strategic decision to focus on petitioner's direct responsibility. Wiggins v. Corcoran, 288 F.3d 629, 639-640 (2002). The court contrasted counsel's complete failure to investigate potential mitigating evidence in Williams, 288 F. 3d, at 640, with the fact that Schlaich and N ethercott knew at least some details of Wiggins' childhood from the PSI and social services records, id., at 641. The court acknowledged that counsel likely knew further investigation "would have resulted in more sordid details surfacing," but agreed with the Maryland Court of Appeals that counsel's knowledge of the avenues of mitigation available to them "was sufficient to make an informed strategic choice" to challenge petitioner's direct responsibility for the murder. Id., at 641-642. The court emphasized that conflicting medical testimony with respect to the time of death, the absence of direct evidence against Wiggins, and unexplained forensic evidence at the crime scene supported counsel's strategy. Id., at 641.
We granted certiorari, 537 U. S. 1027 (2002), and now reverse.
II
A
Petitioner renews his contention that his attorneys' performance at sentencing violated his Sixth Amendment right to effective assistance of counsel. The amendments to 28 U. S. C. § 2254, enacted as part of the Antiterrorism and Effective Death Penalty Act of 1996 (AEDPA), circumscribe our consideration of Wiggins' claim and require us to limit our analysis to the law as it was "clearly established" by our precedents at the time of the state court's decision. Section 2254 provides:"(d) An application for a writ of habeas corpus on behalf of a person in custody pursuant to the judgment of a State court shall not be granted with respect to any claim that was adjudicated on the merits in State court proceedings unless the adjudication of the claim"(1) resulted in a decision that was contrary to, or involved an unreasonable application of, clearly established Federal law, as determined by the Supreme Court of the United States; or"(2) resulted in a decision that was based on an unreasonable determination of the facts in light of the evidence presented in the State court proceeding."
We have made clear that the "unreasonable application" prong of § 2254(d)(1) permits a federal habeas court to "grant the writ if the state court identifies the correct governing legal principle from this Court's decisions but unreasonably applies that principle to the facts" of petitioner's case. Williams v. Taylor, supra, at 413; see also Bell v. Cone, 535 U. S. 685, 694 (2002). In other words, a federal court may grant relief when a state court has misapplied a "governing legal principle" to "a set of facts different from those of the case in which the principle was announced." Lockyer v. Andrade, 538 U. S. 63, 76 (2003) (citing Williams v. Taylor, supra, at 407). In order for a federal court to find a state court's application of our precedent "unreasonable," the state court's decision must have been more than incorrect or erroneous. See Lockyer, supra, at 75. The state court's appli cation must have been "objectively unreasonable." See Williams v. Taylor, 529 U. S., at 409.
We established the legal principles that govern claims of ineffective assistance of counsel in Strickland v. Washington, 466 U. S. 668 (1984). An ineffective assistance claim has two components: A petitioner must show that counsel's performance was deficient, and that the deficiency prejudiced the defense. Id., at 687. To establish deficient performance, a petitioner must demonstrate that counsel's representation "fell below an objective standard of reasonableness." Id., at 688. We have declined to articulate specific guidelines for appropriate attorney conduct and instead have emphasized that "[t]he proper measure of attorney performance remains simply reasonableness under prevailing professional norms." Ibid.
In this case, as in Strickland, petitioner's claim stems from counsel's decision to limit the scope of their investigation into potential mitigating evidence. Id., at 673. Here, as in Strickland, counsel attempt to justify their limited investigation as reflecting a tactical judgment not to present mitigating evidence at sentencing and to pursue an alternative strategy instead. In rejecting the respondent's claim, we defined the deference owed such strategic judgments in terms of the adequacy of the investigations supporting those judgments:"[S]trategic choices made after thorough investigation of law and facts relevant to plausible options are virtually unchallengeable; and strategic choices made after less than complete investigation are reasonable precisely to the extent that reasonable professional judgments support the limitations on investigation. In other words, counsel has a duty to make reasonable investigations or to make a reasonable decision that makes particular investigations unnecessary. In any ineffectiveness case, a particular decision not to investigate must be directly assessed for reasonableness in all the circum stances, applying a heavy measure of deference to counsel's judgments." Id., at 690-691.
Our opinion in Williams v. Taylor is illustrative of the proper application of these standards. In finding Williams' ineffectiveness claim meritorious, we applied Strickland and concluded that counsel's failure to uncover and present voluminous mitigating evidence at sentencing could not be justified as a tactical decision to focus on Williams' voluntary confessions, because counsel had not "fulfill[ed] their obligation to conduct a thorough investigation of the defendant's background." 529 U. S., at 396 (citing 1 ABA Standards for Criminal Justice 4-4.1, commentary, p. 4-55 (2d ed. 1980)). While Williams had not yet been decided at the time the Maryland Court of Appeals rendered the decision at issue in this case, cf. post, at 542 (SCALIA, J., dissenting), Williams' case was before us on habeas review. Contrary to the dissent's contention, post, at 543, we therefore made no new law in resolving Williams' ineffectiveness claim. See Williams, 529 U. S., at 390 (noting that the merits of Williams' claim "are squarely governed by our holding in Strickland"); see also id., at 395 (noting that the trial court correctly applied both components of the Strickland standard to petitioner's claim and proceeding to discuss counsel's failure to investigate as a violation of Strickland's performance prong). In highlighting counsel's duty to investigate, and in referring to the ABA Standards for Criminal Justice as guides, we applied the same "clearly established" precedent of Strickland we apply today. Cf. 466 U. S., at 690-691 (establishing that "thorough investigation[s]" are "virtually unchallengeable" and underscoring that "counsel has a duty to make reasonable investigations"); see also id., at 688-689 ("Prevailing norms of practice as reflected in American Bar Association standards and the like… are guides to determining what is reasonable").
In light of these standards, our principal concern in deciding whether Schlaich and Nethercott exercised "reasonable professional judgmen[t]," id., at 691, is not whether counsel should have presented a mitigation case. Rather, we focus on whether the investigation supporting counsel's decision not to introduce mitigating evidence of Wiggins' background was itself reasonable. Ibid. Cf. Williams v. Taylor, supra, at 415 (O'CONNOR, J., concurring) (noting counsel's duty to conduct the "requisite, diligent" investigation into his client's background). In assessing counsel's investigation, we must conduct an objective review of their performance, measured for "reasonableness under prevailing professional norms," Strickland, 466 U. S., at 688, which includes a context-dependent consideration of the challenged conduct as seen "from counsel's perspective at the time," id., at 689 ("[E]very effort [must] be made to eliminate the distorting effects of hindsight").
B
1
The record demonstrates that counsel's investigation drew from three sources. App. 490-491. Counsel arranged for William Stejskal, a psychologist, to conduct a number of tests on petitioner. Stejskal concluded that petitioner had an IQ of 79, had difficulty coping with demanding situations, and exhibited features of a personality disorder. Id., at 4445, 349-351. These reports revealed nothing, however, of petitioner's life history. Tr. of Oral Arg. 24-25.
With respect to that history, counsel had available to them the written PSI, which included a one-page account of Wiggins' "personal history" noting his "misery as a youth," quoting his description of his own background as "'disgusting,'" and observing that he spent most of his life in foster care. App. 20-21. Counsel also "tracked down" records kept by the Baltimore City Department of Social Services (DSS) documenting petitioner's various placements in the State's foster care system. Id., at 490; Lodging of Petitioner. In describing the scope of counsel's investigation into petitioner's life history, both the Fourth Circuit and the Maryland Court of Appeals referred only to these two sources of information. See 288 F. 3d, at 640-641; Wiggins v. State, 352 Md., at 608609, 724 A. 2d, at 15.
Counsel's decision not to expand their investigation beyond the PSI and the DSS records fell short of the professional standards that prevailed in Maryland in 1989. As Schlaich acknowledged, standard practice in Maryland in capital cases at the time of Wiggins' trial included the preparation of a social history report. App. 488. Despite the fact that the Public Defender's office made funds available for the retention of a forensic social worker, counsel chose not to commission such a report. Id., at 487. Counsel's conduct similarly fell short of the standards for capital defense work articulated by the American Bar Association (ABA)-standards to which we long have referred as "guides to determining what is reasonable." Strickland, supra, at 688; Williams v. Taylor, supra, at 396. The ABA Guidelines provide that investigations into mitigating evidence "should comprise efforts to discover all reasonably available mitigating evidence and evidence to rebut any aggravating evidence that may be introduced by the prosecutor." ABA Guidelines for the Appointment and Performance of Counsel in Death Penalty Cases 11.4.1(C), p. 93 (1989) (emphasis added). Despite these well-defined norms, however, counsel abandoned their investigation of petitioner's background after having acquired only rudimentary knowledge of his history from a narrow set of sources. Cf. id., 11.8.6, p. 133 (noting that among the topics counsel should consider presenting are medical history, educational history, employment and training history, family and social history, prior adult and juvenile correctional experience, and religious and cultural influences (emphasis added)); 1 ABA Standards for Criminal Justice 4-4.1, commentary, p. 4-55 (2d ed. 1982) ("The lawyer also has a substantial and important role to perform in raising mitigating factors both to the prosecutor initially and to the court at sentencing…. Investigation is essential to fulfillment of these functions").
The scope of their investigation was also unreasonable in light of what counsel actually discovered in the DSS records. The records revealed several facts: Petitioner's mother was a chronic alcoholic; Wiggins was shuttled from foster home to foster home and displayed some emotional difficulties while there; he had frequent, lengthy absences from school; and, on at least one occasion, his mother left him and his siblings alone for days without food. See Lodging of Petitioner 54-95, 126, 131-136, 140, 147, 159-176. As the Federal District Court emphasized, any reasonably competent attorney would have realized that pursuing these leads was necessary to making an informed choice among possible defenses, particularly given the apparent absence of any aggravating factors in petitioner's background. 164 F. Supp. 2d, at 559. Indeed, counsel uncovered no evidence in their investigation to suggest that a mitigation case, in its own right, would have been counterproductive, or that further investigation would have been fruitless; this case is therefore distinguishable from our precedents in which we have found limited investigations into mitigating evidence to be reasonable. See, e. g., Strickland, supra, at 699 (concluding that counsel could "reasonably surmise… that character and psychological evidence would be of little help"); Burger v. Kemp, 483 U. S. 776, 794 (1987) (concluding counsel's limited investigation was reasonable because he interviewed all witnesses brought to his attention, discovering little that was helpful and much that was harmful); Darden v. Wainwright, 477 U. S. 168, 186 (1986) (concluding that counsel engaged in extensive preparation and that the decision to present a mitigation case would have resulted in the jury hearing evidence that petitioner had been convicted of violent crimes and spent much of his life in jail). Had counsel investigated further, they might well have discovered the sexual abuse later revealed during state postconviction proceedings. The record of the actual sentencing proceedings underscores the unreasonableness of counsel's conduct by suggesting that their failure to investigate thoroughly resulted from inattention, not reasoned strategic judgment. Counsel sought, until the day before sentencing, to have the proceedings bifurcated into a retrial of guilt and a mitigation stage. See supra, at 515. On the eve of sentencing, counsel represented to the court that they were prepared to come forward with mitigating evidence, App. 45, and that they intended to present such evidence in the event the court granted their motion to bifurcate. In other words, prior to sentencing, counsel never actually abandoned the possibility that they would present a mitigation defense. Until the court denied their motion, then, they had every reason to develop the most powerful mitigation case possible.
What is more, during the sentencing proceeding itself, counsel did not focus exclusively on Wiggins' direct responsibility for the murder. After introducing that issue in her opening statement, id., at 70-71, Nethercott entreated the jury to consider not just what Wiggins "is found to have done," but also "who [he] is." Id., at 70. Though she told the jury it would "hear that Kevin Wiggins has had a difficult life," id., at 72, counsel never followed up on that suggestion with details of Wiggins' history. At the same time, counsel called a criminologist to testify that inmates serving life sentences tend to adjust well and refrain from further violence in prison-testimony with no bearing on whether petitioner committed the murder by his own hand. Id., at 311-312. Far from focusing exclusively on petitioner's direct responsibility, then, counsel put on a halfhearted mitigation case, taking precisely the type of " 'shotgun'" approach the Maryland Court of Appeals concluded counsel sought to avoid. Wig gins v. State, 352 Md., at 609, 724 A. 2d, at 15. When viewed in this light, the "strategic decision" the state courts and respondents all invoke to justify counsel's limited pursuit of mitigating evidence resembles more a post hoc rationaliza tion of counsel's conduct than an accurate description of their deliberations prior to sentencing.
In rejecting petitioner's ineffective assistance claim, the Maryland Court of Appeals appears to have assumed that because counsel had some information with respect to petitioner's background-the information in the PSI and the DSS records-they were in a position to make a tactical choice not to present a mitigation defense. Id., at 611-612, 724 A. 2d, at 17 (citing federal and state precedents finding ineffective assistance in cases in which counsel failed to conduct an investigation of any kind). In assessing the reasonableness of an attorney's investigation, however, a court must consider not only the quantum of evidence already known to counsel, but also whether the known evidence would lead a reasonable attorney to investigate further. Even assuming Schlaich and Nethercott limited the scope of their investigation for strategic reasons, Strickland does not establish that a cursory investigation automatically justifies a tactical decision with respect to sentencing strategy. Rather, a reviewing court must consider the reasonableness of the investigation said to support that strategy. 466 U. S., at 691.
The Maryland Court of Appeals' application of Strickland's governing legal principles was objectively unreasonable. Though the state court acknowledged petitioner's claim that counsel's failure to prepare a social history "did not meet the minimum standards of the profession," the court did not conduct an assessment of whether the decision to cease all investigation upon obtaining the PSI and the DSS records actually demonstrated reasonable professional judgment. Wiggins v. State, 352 Md., at 609, 724 A. 2d, at 16. The state court merely assumed that the investigation was adequate. In light of what the PSI and the DSS records actually revealed, however, counsel chose to abandon their investigation at an unreasonable juncture, making a fully informed decision with respect to sentencing strategy impossible. The Court of Appeals' assumption that the investigation was adequate, ibid., thus reflected an unreasonable application of Strickland. 28 U. S. C. § 2254(d)(1). As a result, the court's subsequent deference to counsel's strategic decision not "to present every conceivable mitigation defense," 352 Md., at 610, 724 A. 2d, at 16, despite the fact that counsel based this alleged choice on what we have made clear was an unreasonable investigation, was also objectively unreasonable. As we established in Strickland, "strategic choices made after less than complete investigation are reasonable precisely to the extent that reasonable professional judgments support the limitations on investigation." 466 U. S., at 690-691.
Additionally, the court based its conclusion, in part, on a clear factual error-that the "social service records… recorded incidences of… sexual abuse." 352 Md., at 608-609, 724 A. 2d, at 15. As the State and the United States now concede, the records contain no mention of sexual abuse, much less of the repeated molestations and rapes of petitioner detailed in the Selvog report. Brief for Respondents 22; Brief for United States as Amicus Curiae 26; App. to Pet. for Cert. 175a-179a, 190a. The state court's assumption that the records documented instances of this abuse has been shown to be incorrect by "clear and convincing evidence," 28 U. S. C. § 2254(e)(1), and reflects "an unreasonable determination of the facts in light of the evidence presented in the State court proceeding," § 2254(d)(2). This partial reliance on an erroneous factual finding further highlights the unreasonableness of the state court's decision.
The dissent insists that this Court's hands are tied, under § 2254(d), "by the state court's factual determinations that Wiggins' trial counsel 'did investigate and were aware of [Wiggins'] background,'" post, at 550. But as we have made clear, the Maryland Court of Appeals' conclusion that the scope of counsel's investigation into petitioner's background met the legal standards set in Strickland repre sented an objectively unreasonable application of our precedent. § 2254(d)(1). Moreover, the court's assumption that counsel learned of a major aspect of Wiggins' background, i. e., the sexual abuse, from the DSS records was clearly erroneous. The requirements of § 2254(d) thus pose no bar to granting petitioner habeas relief.