NOTICE: This opinion is subject to formal revision before publication in the preliminary print of the United States Reports. Readers are requested to notify the Reporter of Decisions, Supreme Court of the United States, Washington, D. C. 20543, of any typographical or other formal errors, in order that corrections may be made before the preliminary print goes to press.
SUPREME COURT OF THE UNITED STATES
_________________
No. 13–1433
_________________
KEVAN BRUMFIELD, PETITIONER
v.BURL CAIN, WARDEN
on writ of certiorari to the united states court of appeals for the fifth circuit
[June 18, 2015]
Justice Sotomayor delivered the opinion of the Court.
In
Atkins v.
Virginia,
536 U. S. 304 (2002)
, this Court recognized that the execution of the intellectually disabled contravenes the
Eighth Amendment’s prohibition on cruel and unusual punishment. After
Atkins was decided, petitioner, a Louisiana death-row inmate, requested an opportunity to prove he was intellectually disabled in state court. Without affording him an evidentiary hearing or granting him time or funding to secure expert evidence, the state court rejected petitioner’s claim. That decision, we hold, was “based on an unreasonable determination of the facts in light of the evidence presented in the State court proceeding.”
28 U. S. C. §2254(d)(2). Petitioner was therefore entitled to have his
Atkins claim considered on the merits in federal court.
I
Petitioner Kevan Brumfield was sentenced to death for the 1993 murder of off-duty Baton Rouge police officer Betty Smothers. Brumfield, accompanied by another individual, shot and killed Officer Smothers while she was escorting the manager of a grocery store to the bank.
At the time of Brumfield’s trial, this Court’s precedent permitted the imposition of the death penalty on intellectually disabled persons. See
Penry v.
Lynaugh,
492 U. S. 302,
340 (1989)
(opinion of O’Connor, J.). But in
Atkins, this Court subsequently held that “in light of . . . ‘evolving standards of decency,’ ” the
Eighth Amendment “ ‘places a substantive restriction on the State’s power to take the life’ of a mentally retarded offender.” 536 U. S., at 321 (quoting
Ford v.
Wainwright,
477 U. S. 399,
405 (1986)
).[
1] Acknowledging the “disagreement” regarding how to “determin[e] which offenders are in fact” intellectually disabled, the Court left “to the State[s] the task of developing appropriate ways to enforce the constitutional restriction upon [their] execution of sentences.” 536 U. S., at 317 (internal quotation marks omitted; some alterations in original).
The Louisiana Supreme Court took up the charge of implementing
Atkins’ mandate in
State v.
Williams, 2001–1650 (La. 11/1/02), 831 So. 2d 835. The court held that “a diagnosis of mental retardation has three distinct components: (1) subaverage intelligence, as measured by objective standardized IQ tests; (2) significant impairment in several areas of adaptive skills; and (3) manifestations of this neuro-psychological disorder in the developmental stage.”
Id., at 854 (relying on,
inter alia, American Association of Mental Retardation, Mental Retardation: Definition, Classification, and Systems of Supports (10th ed. 2002) (AAMR), and American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders (rev. 4th ed. 2000) (DSM–IV)); see also La. Code Crim. Proc. Ann., Art. 905.5.1(H)(1) (West Cum. Supp. 2015) (subsequently enacted statute governing
Atkins claims adopting the three
Williams criteria). The
Williams court also clarified that “not everyone faced with a death pen-alty sentence” would “automatically be entitled to a post-
Atkins hearing”; rather, it would “be an individual defendant’s burden to provide objective factors that will put at issue the fact of mental retardation.” 831 So. 2d, at 857. Borrowing from the state statutory standard for determining when a pretrial competency inquiry is necessary, the court held that an
Atkins evidentiary hearing is required when an inmate has put forward sufficient evidence to raise a “ ‘reasonable ground’ ” to believe him to be intellectually disabled. See
id., at 861; see also
id., at 858, n. 33 (characterizing the requisite showing as one raising a “ ‘reasonable doubt’ ”).[
2]
Shortly after the
Williams decision, Brumfield amended his pending state postconviction petition to raise an
Atkins claim. He sought an evidentiary hearing on the issue, asserting that his case was “accompanied by a host of objective facts which raise the issue of mental retardation.” App. 203a.
In support, Brumfield pointed to mitigation evidence introduced at the sentencing phase of his trial. He focused on the testimony of three witnesses in particular: his mother; Dr. Cecile Guin, a social worker who had compiled a history of Brumfield by consulting available records and conducting interviews with family members and teachers; and Dr. John Bolter, a clinical neuropsychologist who had performed a number of cognitive tests on Brumfield. A psychologist, Dr. Brian Jordan, had also examined Brumfield and prepared a report, but did not testify at trial. Brumfield contended that this evidence showed, among other things, that he had registered an IQ score of 75, had a fourth-grade reading level, had been prescribed numerous medications and treated at psychiatric hospitals as a child, had been identified as having some form of learning disability, and had been placed in special education classes. See
id., at 203a–204a. Brumfield further requested “all the resources necessary to the proper presentation of his case,” asserting that until he was able to “retain the services of various experts,” it would be “premature for [the court] to address [his] claims.”
Id., at 207a.
Without holding an evidentiary hearing or granting funds to conduct additional investigation, the state trial court dismissed Brumfield’s petition. With respect to the request for an
Atkins hearing, the court stated:
“I’ve looked at the application, the response, the record, portions of the transcript on that issue, and the evidence presented, including Dr. Bolter’s testimony, Dr. Guinn’s [
sic] testimony, which refers to and discusses Dr. Jordan’s report, and based on those, since this issue—there was a lot of testimony by all of those in Dr. Jordan’s report.
“Dr. Bolter in particular found he had an IQ of over—or 75. Dr. Jordan actually came up with a little bit higher IQ. I do not think that the defendant has demonstrated impairment based on the record in adaptive skills. The doctor testified that he did have an anti-social personality or sociopath, and explained it as someone with no conscience, and the defendant hadn’t carried his burden placing the claim of mental retardation at issue. Therefore, I find he is not entitled to that hearing based on all of those things that I just set out.” App. to Pet. for Cert. 171a–172a.
After the Louisiana Supreme Court summarily denied his application for a supervisory writ to review the trial court’s ruling,
Brumfield v.
State, 2004–0081 (La. 10/29/04), 885 So. 2d 580, Brumfield filed a petition for habeas corpus in federal court, again pressing his
Atkins claim. Pursuant to the Antiterrorism and Effective Death Penalty Act of 1996 (AEDPA), Brumfield could secure relief only if the state court’s rejection of his claim was either “contrary to, or involved an unreasonable application of, clearly established Federal law, as determined by the Supreme Court of the United States,” or was “based on an unreasonable determination of the facts in light of the evidence presented in the State court proceeding.” 28 U. S. C. §§2254(d)(1), (2).
The District Court found that both of these requirements had been met. 854 F. Supp. 2d 366, 383–384 (MD La. 2012). First, the District Court held that denying Brumfield an evidentiary hearing without first granting him funding to develop his
Atkins claim “represented an unreasonable application of then-existing due process law,” thus satisfying §2254(d)(1).
Id., at 379. Second, and in the alternative, the District Court found that the state court’s decision denying Brumfield a hearing “suffered from an unreasonable determination of the facts in light of the evidence presented in the state habeas proceeding in violation of §2254(d)(2).”
Ibid.
The District Court further determined Brumfield to be intellectually disabled based on the extensive evidence it received during an evidentiary hearing.
Id., at 406; see
Cullen v.
Pinholster,
563 U. S. 170
, ___ (2011) (slip op., at 13) (recognizing that federal habeas courts may “take new evidence in an evidentiary hearing” when §2254(d) does not bar relief). This evidence included the results of various IQ tests—which, when adjusted to account for measurement errors, indicated that Brumfield had an IQ score between 65 and 70, 854 F. Supp. 2d, at 392—testimony and expert reports regarding Brumfield’s adaptive behavior and “significantly limited conceptual skills,”
id., at 401, and proof that these deficits in intellectual functioning had exhibited themselves before Brumfield reached adulthood,
id., at 405. Thus, the District Court held, Brumfield had “demonstrated he is mentally retarded as defined by Louisiana law” and was “ineligible for execution.”
Id., at 406.
The United States Court of Appeals for the Fifth Circuit reversed. 744 F. 3d 918, 927 (2014). It held that Brumfield’s federal habeas petition failed to satisfy either of §2254(d)’s requirements. With respect to the District Court’s conclusion that the state court had unreasonably applied clearly established federal law, the Fifth Circuit rejected the notion that any of this Court’s precedents required a state court to grant an
Atkins claimant the funds necessary to make a threshold showing of intellectual disability. See 744 F. 3d, at 925–926. As for the District Court’s holding that the state court’s decision rested on an unreasonable determination of the facts, the Fifth Circuit declared that its “review of the record persuad[ed it] that the state court did not abuse its discretion when it denied Brumfield an evidentiary hearing.”
Id., at 926. Having found that Brumfield’s petition failed to clear §2254(d)’s hurdle, the Fifth Circuit did not review the District Court’s conclusion that Brumfield is, in fact, intellectually disabled. See
id., at 927, and n. 8.
We granted certiorari on both aspects of the Fifth Circuit’s §2254(d) analysis, 574 U. S. ___ (2014), and now vacate its decision and remand for further proceedings.
II
Before this Court, Brumfield advances both of the rationales on which the District Court relied in holding §2254(d) to be satisfied. Because we agree that the state court’s rejection of Brumfield’s request for an
Atkins hearing was premised on an “unreasonable determination of the facts” within the meaning of §2254(d)(2), we need not address whether its refusal to grant him expert funding, or at least the opportunity to seek
pro bono expert assistance to further his threshold showing, reflected an “unreasonable application of . . . clearly established Federal law,” §2254(d)(1).
In conducting the §2254(d)(2) inquiry, we, like the courts below, “look through” the Louisiana Supreme Court’s summary denial of Brumfield’s petition for review and evaluate the state trial court’s reasoned decision refusing to grant Brumfield an
Atkins evidentiary hearing. See
Johnson v.
Williams, 568 U. S. ___, ___, n. 1 (2013) (slip op., at 6, n. 1);
Ylst v.
Nunnemaker,
501 U. S. 797,
806 (1991)
. Like Brumfield, we do not question the propriety of the legal standard the trial court applied, and presume that a rule according an evidentiary hearing only to those capital defendants who raise a “reasonable doubt” as to their intellectual disability is consistent with our decision in
Atkins. Instead, we train our attention on the two underlying factual determinations on which the trial court’s decision was premised—that Brumfield’s IQ score was inconsistent with a diagnosis of intellectual disability and that he had presented no evidence of adaptive impairment. App. to Pet. for Cert. 171a–172a.[
3]
We may not characterize these state-court factual determinations as unreasonable “merely because [we] would have reached a different conclusion in the first instance.”
Wood v.
Allen,
558 U. S. 290,
301 (2010)
. Instead, §2254(d)(2) requires that we accord the state trial court substantial deference. If “ ‘[r]easonable minds reviewing the record might disagree’ about the finding in question, ‘on habeas review that does not suffice to supersede the trial court’s . . . determination.’ ”
Ibid. (quoting
Rice v.
Collins,
546 U. S. 333
–342 (2006)). As we have also observed, however, “[e]ven in the context of federal habeas, deference does not imply abandonment or abdication of judicial review,” and “does not by definition preclude relief.”
Miller-El v.
Cockrell,
537 U. S. 322,
340 (2003)
. Here, our examination of the record before the state court compels us to conclude that both of its critical factual determinations were unreasonable.
A
The state trial court’s rejection of Brumfield’s request for an
Atkins hearing rested, first, on Dr. Bolter’s testi-mony that Brumfield scored 75 on an IQ test and may have scored higher on another test. See App. to Pet. for Cert. 171a. These scores, the state court apparently believed, belied the claim that Brumfield was intellectually disabled because they necessarily precluded any possibility that he possessed subaverage intelligence—the first of the three criteria necessary for a finding of intellectual disability. But in fact, this evidence was entirely consistent with intellectual disability.
To qualify as “significantly subaverage in general intellectual functioning” in Louisiana, “one must be more than two standard deviations below the mean for the test of intellectual functioning.”
Williams, 831 So. 2d, at 853 (internal quotation marks omitted). On the Wechsler scale for IQ—the scale employed by Dr. Bolter—that would equate to a score of 70 or less. See
id., at 853–854, n. 26.
As the Louisiana Supreme Court cautioned in
Williams, however, an IQ test result cannot be assessed in a vac-uum. In accord with sound statistical methods, the court explained: “[T]he assessment of intellectual functioning through the primary reliance on IQ tests must be tempered with attention to possible errors in measurement.”
Ibid. Thus,
Williams held, “[a]lthough Louisiana’s definition of significantly subaverage intellectual functioning does not specifically use the word ‘approximately,’ because of the SEM [(standard error of measurement)], any IQ test score has a margin of error and is only a factor in assessing mental retardation.”
Id., at 855, n. 29.
Accounting for this margin of error, Brumfield’s reported IQ test result of 75 was squarely in the range of potential intellectual disability. The sources on which
Williams relied in defining subaverage intelligence both describe a score of 75 as being consistent with such a diagnosis. See AAMR, at 59; DSM–IV, at 41–42; see also
State v.
Dunn, 2001–1635 (La. 5/11/10), 41 So. 3d 454, 470 (“The ranges associated with the two scores of 75 brush the threshold score for a mental retardation diagnosis”).[
4] Relying on similar authorities, this Court observed in
Atkins that “an IQ between 70 and 75 or lower . . . is typically considered the cutoff IQ score for the intellectual function prong of the mental retardation definition.” 536 U. S., at 309, n. 5. Indeed, in adopting these definitions, the Louisiana Supreme Court anticipated our holding in
Hall v.
Florida, 572 U. S. ___ (2014), that it is unconstitutional to foreclose “all further exploration of intellectual disability” simply because a capital defendant is deemed to have an IQ above 70.
Id., at ___ (slip op., at 1); see also
id., at ___ (slip op., at 12) (“For professionals to diagnose—and for the law then to determine—whether an intellectual disability exists once the SEM applies and the individual’s IQ score is 75 or below the inquiry would consider factors indicating whether the person had deficits in adaptive functioning”). To conclude, as the state trial court did, that Brumfield’s reported IQ score of 75 somehow demonstrated that he could not possess subaverage intelligence therefore reflected an unreasonable determination of the facts.
Nor was there evidence of any higher IQ test score that could render the state court’s determination reasonable. The state court claimed that Dr. Jordan, who examined Brumfield but never testified at trial, “came up with a little bit higher IQ.” App. to Pet. for Cert. 171a. At trial, the existence of such a test score was mentioned only during the cross-examination of Dr. Bolter, who had sim-ply acknowledged the following: “Dr. Jordan rated his intelligence just a little higher than I did. But Dr. Jordan also only did a screening test and I gave a standardized measure of intellectual functioning.” App. 133a. And in fact, Dr. Jordan’s written report provides no IQ score. See
id., at 429a.[
5] The state court therefore could not reason-ably infer from this evidence that any examination Dr. Jordan had performed was sufficiently rigorous to preclude definitively the possibility that Brumfield possessed subaverage intelligence. See
State v.
Dunn, 2001–1635 (La. 11/1/02), 831 So. 2d 862, 886, n. 9 (ordering
Atkins evidentiary hearing even though “prison records indicate[d]” the defendant had an “ ‘estimated IQ of 76,’ ” emphasizing testimony that prison officials “did not do the formal IQ testing”).
B
The state court’s refusal to grant Brumfield’s request for an
Atkins evidentiary hearing rested, next, on its con-clusion that the record failed to raise any question as to Brumfield’s “impairment . . . in adaptive skills.” App. to Pet. for Cert. 171a. That determination was also unreasonable.
The adaptive impairment prong of an intellectual dis-ability diagnosis requires an evaluation of the individual’s ability to function across a variety of dimensions. The Louisiana Supreme Court in
Williams described three separate sets of criteria that may be utilized in making this assessment. See 831 So. 2d, at 852–854. Although Louisiana courts appear to utilize all three of these tests in evaluating adaptive impairment, see
Dunn, 41 So. 3d, at 458–459, 463, for the sake of simplicity we will assume that the third of these tests, derived from Louisiana statutory law, governed here, as it appears to be the most favorable to the State.[
6] Under that standard, an individual may be intellectually disabled if he has “substantial functional limitations in three or more of the following areas of major life activity: (i) Self-care. (ii) Understanding and use of language. (iii) Learning. (iv) Mobility. (v) Self-direction. (vi) Capacity for independent living.”
Williams, 831 So. 2d, at 854 (quoting then La. Rev. Stat. Ann. §28:381(12) (repealed 2005)).
The record before the state court contained sufficient evidence to raise a question as to whether Brumfield met these criteria. During the sentencing hearing, Brumfield’s mother testified that Brumfield had been born prematurely at a very low birth weight. App. 28a. She also recounted that he had been taken out of school in the fifth grade and hospitalized due to his behavior, and recalled an incident in which he suffered a seizure.
Id., at 34a–38a, 41a, 47a.
Social worker Dr. Guin elaborated on this testimony, explaining that Brumfield’s low birth weight indicated “that something ha[d] gone wrong during the pregnancy,” that medical records suggested Brumfield had “slower responses than normal babies,” and that “they knew that something was wrong at that point.”
Id., at 75a–76a. Dr. Guin also confirmed that, beginning in fifth grade, Brumfield had been placed in special classes in school and in multiple mental health facilities, and had been prescribed antipsychotics and sedatives.
Id., at 89a, 93a–94a.[
7] Moreover, one report Dr. Guin reviewed from a facility that treated Brumfield as a child “questioned his intellectual functions,” and opined that “he probably had a learning disability related to some type of slowness in motor development, some type of physiological [problem].”
Id., at 89a. Dr. Guin herself reached a similar conclusion, stating that Brumfield “obviously did have a physiologically linked learning disability that he was born with,” and that his “basic problem was that he . . . could not process information.”
Id., at 90a, 98a.
Finally, Dr. Bolter, who had performed “a comprehensive battery of tests,” confirmed that Brumfield had a “borderline general level of intelligence.”
Id., at 127a–128a. His low intellect manifested itself in a fourth-grade reading level—and he reached that level, Dr. Bolter elaborated, only with respect to “simple word recognition,” and “not even comprehension.”
Id., at 128a; see also
id., at 134a. In a written report submitted to the state court, Dr. Bolter further noted that Brumfield had deficiencies “frequently seen in individuals with a history of learning disabilities,” and “clearly” had “learning characteristics that make it more difficult for him to acquire new information.”
Id., at 418a, 420a. Dr. Bolter also testified that Brumfield’s low birth weight had “place[d] him [at] a risk of some form of potential neurological trauma,” and affirmed that the medications administered to Brumfield as a child were generally reserved for “severe cases.”
Id., at 130a, 132a.
All told, then, the evidence in the state-court record provided substantial grounds to question Brumfield’s adaptive functioning. An individual, like Brumfield, who was placed in special education classes at an early age, was suspected of having a learning disability, and can barely read at a fourth-grade level, certainly would seem to be deficient in both “[u]nderstanding and use of language” and “[l]earning”—two of the six “areas of major life activity” identified in
Williams. 831 So. 2d, at 854. And the evidence of his low birth weight, of his commitment to mental health facilities at a young age, and of officials’ administration of antipsychotic and sedative drugs to him at that time, all indicate that Brumfield may well have had significant deficits in at least one of the remaining four areas. See
ibid.
In advancing its contrary view of the record, the state court noted that Dr. Bolter had described Brumfield as someone with “an antisocial personality.” App. 127a; see App. to Pet. for Cert. 171a. The relevance of this diagnosis is, however, unclear, as an antisocial personality is not inconsistent with any of the above-mentioned areas of adaptive impairment, or with intellectual disability more generally. The DSM–IV—one of the sources on which the
Williams court relied in defining intellectual disability—provides: “The diagnostic criteria for Mental Retardation do not include an exclusion criterion; therefore, the diagnosis should be made . . . regardless of and in addition to the presence of another disorder.” DSM–IV, at 47; see also AAMR, at 172 (noting that individuals with intellectual disability also tend to have a number of other mental health disorders, including personality disorders).
To be sure, as the dissent emphasizes,
post, at 13–14, 18, other evidence in the record before the state court may have cut against Brumfield’s claim of intellectual disability. Perhaps most significant, in his written report Dr. Bolter stated that Brumfield “appears to be normal from a neurocognitive perspective,” with a “normal capacity to learn and acquire information when given the opportunity for repetition,” and “problem solving and reasoning skills” that were “adequate.” App. 421a. Likewise, the underlying facts of Brumfield’s crime might arguably provide reason to think that Brumfield possessed certain adaptive skills, as the murder for which he was convicted required a degree of advanced planning and involved the acquisition of a car and guns. But cf. AAMR, at 8 (intellectually disabled persons may have “strengths in social or physical capabilities, strengths in some adaptive skill areas, or strengths in one aspect of an adaptive skill in which they otherwise show an overall limitation”).
It is critical to remember, however, that in seeking an evidentiary hearing, Brumfield was not obligated to show that he was intellectually disabled, or even that he would likely be able to prove as much. Rather, Brumfield needed only to raise a “reasonable doubt” as to his intellectual disability to be entitled to an evidentiary hearing. See
Williams, 831 So. 2d, at 858, n. 33. The Louisiana Supreme Court’s decision in
Williams illustrated how low the threshold for an evidentiary hearing was intended to be: There, the court held that the defendant was entitled to a hearing on his
Atkins claim notwithstanding the fact that “the defense’s own expert testified unequivocally, at both the guilt and penalty phases of trial, that [the] defendant is not mentally retarded,” an assessment “based on the fact that [the] defendant [was] not deficient in adaptive functioning.” 831 So. 2d, at 855; see also
Dunn, 831 So. 2d, at 885, 887 (ordering hearing despite expert testimony that the defendant “had never been identified as a child who was a slow learner,” and had “received college credit for courses completed during his incarceration”). Similarly, in light of the evidence of Brumfield’s deficiencies, none of the countervailing evidence could be said to foreclose all reasonable doubt. An individual who points to evidence that he was at risk of “neurological trauma” at birth, was diagnosed with a learning disability and placed in special education classes, was committed to mental health facilities and given powerful medication, reads at a fourth-grade level, and simply cannot “process information,” has raised substantial reason to believe that he suffers from adaptive impairments.
That these facts were alone sufficient to raise a doubt as to Brumfield’s adaptive impairments is all the more apparent given that Brumfield had not yet had the opportunity to develop the record for the purpose of proving an intellectual disability claim. At his pre-
Atkins trial, Brumfield had little reason to investigate or present evidence relating to intellectual disability. In fact, had he done so at the penalty phase, he ran the risk that it would “enhance the likelihood . . . future dangerousness [would] be found by the jury.”
Atkins, 536 U. S., at 321. Thus, given that the evidence from trial provided good reason to think Brumfield suffered from an intellectual disability, there was even greater cause to believe he might prove such a claim in a full evidentiary hearing. Indeed, the Louisiana Supreme Court had made clear that a capital defendant in Brumfield’s position should be accorded this additional benefit of the doubt when it defined the standard for assessing whether a hearing is required. Echoing
Atkins’ observation that penalty-phase evidence of intellectual disability can be a “two-edged sword,”
ibid.,
Williams noted that where a trial “was conducted prior to
Atkins,” the defense’s “trial strategy may have been to shift the focus away from any diagnosis of mental retardation.” 831 So. 2d, at 856, n. 31. For that reason, the
Williams court considered the fact that the defendant “ha[d] not had the issue of mental retardation put before the fact finder in light of the
Atkins restriction on the death penalty” as a factor supporting the requisite threshold showing that “entitled [him] to an evidentiary hearing.”
Id., at 857; accord,
Dunn, 831 So. 2d, at 886. Here, the state trial court should have taken into account that the evidence before it was sought and introduced at a time when Brumfield’s intellectual disability was not at issue. The court’s failure to do so resulted in an unreasonable determination of the facts.
III
A
Urging affirmance of the decision below, the State advances two additional arguments that we need discuss only briefly.
First, the State suggests that rather than being evaluated pursuant to §2254(d)(2)’s “unreasonable determination of the facts” standard, Brumfield’s attack on the state trial court’s decision should instead be “ ‘reviewed under the arguably more deferential standard set out in §2254(e)(1).’ ” Brief for Respondent 30 (quoting
Wood, 558 U. S., at 301).[
8] We have not yet “defined the precise relationship between §2254(d)(2) and §2254(e)(1),”
Burt v.
Titlow, 571 U. S. ___, ___ (2013) (slip op., at 5), and we need not do so here. The State did not press below the theory that §2254(e)(1) supplies the governing standard when a court evaluates whether a habeas petitioner has satisfied §2254(d)(2)’s requirements, the Fifth Circuit did not address that possibility, and the State in its brief in opposition to certiorari failed to advance any specific argument that the decision below could be supported by invocation of that statutory provision. See Brief in Opposition 60–64. The argument is therefore “properly ‘deemed waived.’ ”
Granite Rock Co. v.
Teamsters,
561 U. S. 287,
306 (2010)
(quoting this Court’s Rule 15.2).
Second, the State contends that Brumfield’s request for an
Atkins hearing was properly rejected because the record evidence failed to show that Brumfield’s intellectual deficiencies manifested while he was in the “developmental stage”—that is, before he reached adulthood.
Williams, 831 So. 2d, at 854. But the state trial court never made any finding that Brumfield had failed to produce evidence suggesting he could meet this age-of-onset requirement. There is thus no determination on that point to which a federal court must defer in assessing whether Brumfield satisfied §2254(d). See
Panetti v.
Quarterman,
551 U. S. 930
–954 (2007); compare,
e.g.,
Wiggins v.
Smith,
539 U. S. 510,
534 (2003)
(reviewing
de novo the question whether petitioner had suffered prejudice where state court’s reasoned decision rejecting claim under
Strickland v.
Washington,
466 U. S. 668 (1984)
, was premised solely on conclusion that attorney’s performance had not been constitutionally deficient), with
Harrington v.
Richter,
562 U. S. 86,
98 (2011)
(requiring federal habeas court to defer to hypothetical reasons state court might have given for rejecting federal claim where there is no “opinion explaining the reasons relief has been denied”). In any event, the state-court record contained ample evidence creating a reasonable doubt as to whether Brumfield’s disability manifested before adulthood: Both Dr. Guin and Dr. Bolter testified at length about Brumfield’s intellectual shortcomings as a child and their possible connection to his low birth weight. If Brumfield presented sufficient evidence to suggest that he was intellectually limited, as we have made clear he did, there is little question that he also established good reason to think that he had been so since he was a child.
B
Finally, we offer a few additional words in response to Justice Thomas’ dissent. We do not deny that Brumfield’s crimes were terrible, causing untold pain for the victims and their families. But we are called upon today to resolve a different issue. There has already been one death that society rightly condemns. The question here is whether Brumfield cleared AEDPA’s procedural hurdles, and was thus entitled to a hearing to show that he so lacked the capacity for self-determination that it would violate the
Eighth Amendment to permit the State to impose the “law’s most severe sentence,”
Hall, 572 U. S., at ___ (slip op., at 7), and take his life as well. That question, and that question alone, we answer in the affirmative.
* * *
We hold that Brumfield has satisfied the requirements of §2254(d). The judgment of the United States Court of Appeals for the Fifth Circuit is therefore vacated, and the case is remanded for further proceedings consistent with this opinion.
It is so ordered.