United States v. Wilson (170 F. Supp. 3d 347, 2016)

United States District Court for the Eastern District of New York 2016-03-15

Crimes and Criminal Procedure

Citations

Full opinion text

MEMORANDUM & ORDER

NICHOLAS G. GARAUFIS, United States District Judge

On February 7, 2013, the court found that Defendant Ronell Wilson was not intellectually disabled and, therefore, was eligible to receive the death penalty for the 2003 murder of two undercover police detectives. See United States v. Wilson, 922 F.Supp.2d 334 (E.D.N.Y.2013) (“Wilson II”). In reaching that decision, the court determined that Wilson had failed to show that he suffered from significantly subaverage intellectual functioning, a necessary prerequisite to a finding of intellectual disability. Id. at 368. Accordingly, the court declined to consider other requirements for a finding of intellectual disability — namely, whether Wilson suffered from significant deficits in adaptive functioning. Id. On July 24, 2013, a jury returned a unanimous verdict of death. (July 24, 2013, Special Jury Verdict Form (Dkt. 1437).) Consistent with this verdict, the court sentenced Wilson to death on September 11, 2013. (Addendum to J. & Order (Dkt. 1469).)

On June 25, 2014, the Second Circuit issued an order, sua sponte, remanding Wilson’s case to this court to “reconsider its decision that Wilson is not intellectually disabled, in light of Hall v. Florida, — U.S. -, 134 S.Ct. 1986, 188 L.Ed.2d 1007 (2014).” United States v. Wilson, 571 Fed.Appx. 19, 19 (2d Cir.2014) (Mem.) (internal citations omitted). The Second Circuit further instructed:

The District Court should address whether it needs to consider evidence of Wilson’s adaptive deficits given Wilson’s IQ scores. The District Court may consider any other issue it deems appropriate and conduct additional factfinding if warranted. We express no opinion regarding how, if at all, Hall affects the District Court’s original analysis.

Id. at 19-20.

Here, the court interprets Hall as holding that, where application of the standard error measurement with a confidence interval of 95% results in a range of possible intelligence quotient (“IQ”) test scores that reach 70 or below, the defendant has demonstrated that he or she suffers from significantly subaverage intellectual functioning. Under this interpretation, Wilson has satisfied this first requirement; therefore, the court must consider evidence of Wilson’s adaptive functioning in order to determine whether he is intellectually disabled. For the reasons stated below, the court finds that Wilson has demonstrated significant deficits in adaptive functioning, and he therefore meets the legal standard for proving intellectual disability. Accordingly, Wilson is ineligible to receive the death sentence that has been imposed on him.

I. BACKGROUND

A. Procedural History

The court presumes familiarity with the facts of this case. However, an overview of the procedural history is in order. On December 20, 2006, a jury convicted Wilson of five capital counts stemming from his 2003 robbery and murder of New York Police Department detectives James Nem-orin and Rodney Andrews. (Jury Verdict (Dkt. 351); see also Second Superseding Indictment (Dkt. 179) ¶¶ 7, 9.) The same jury voted unanimously to impose the death penalty (Jan. 30, 2007, Special Jury Verdict Form (Dkt. 360)), and the court accordingly sentenced Wilson to death (J. (Dkt. 407)). On appeal, the Second Circuit affirmed Wilson’s convictions but vacated his death sentence on the ground that the penalty proceeding had been corrupted by prosecutorial misconduct. United States v. Whitten, 610 F.3d 168 (2d Cir.2010). The circuit court remanded the case to this court for a retrial of the penalty phase. Id. at 205.

On remand, Wilson argued that he was intellectually disabled and, therefore, ineligible for the death penalty under the Eighth Amendment, see Atkins v. Virginia, 536 U.S. 304, 122 S.Ct. 2242, 153 L.Ed.2d 335 (2002), and the Federal Death Penalty Act (the “FDPA”), 18 U.S.C. § 3596(c). After a nine-day evidentiary hearing (the “Atkins hearing”) (Atkins Hr’g Tr. (“Tr.”) (Dkts. 1002, 1008, 1528-30, 1531-34)), and the submission of post-hearing briefs (Def.’s Mem. (Dkt. 982); Gov’t’s Mem. (Dkt. 984); Def.’s Reply (Dkt. 999)), the court found that Wilson was not intellectually disabled, because his IQ scores indicated sufficient intellectual functioning. Wilson II, 922 F.Supp.2d at 368. As a result, the court did not consider evidence of deficits in Wilson’s adaptive functioning. Id. Wilson proceeded to a second penalty trial before a new jury. The second jury also voted unanimously to impose the death penalty (July 24, 2013, Special Jury Verdict Form), and the court again sentenced Wilson to death (Addendum to J. & Order).

On May 27, 2014, the Supreme Court issued its decision in Hall v. Florida. In that case, the petitioner challenged a Florida law that foreclosed further exploration of a capital defendant’s purported intellectual disability if his or her IQ score was greater than 70. 134 S.Ct. at 1990. The Florida Supreme Court had affirmed the lower court ruling that Hall was not intellectually disabled, based on his IQ scores above 70, without conducting further analysis. Id. at 1992. The U.S. Supreme Court noted that Florida law conflicted with the majority of states that had rejected strict IQ score cutoffs in favor of considering a score’s “standard error of measurement,” or “SEM.” Id. at 1996. The Court also observed that Florida’s approach disregarded the “unanimous professional consensus” in the medical field that IQ scores should be read not as a single fixed number but as a range quantified by the SEM. Id. at 2000. Accordingly, the Court held that Florida’s strict cutoff rule created an “unacceptable risk that persons with intellectual disability will be executed,” in violation of the Eighth Amendment. Id. at 1990. The Court further declared that “[b]y failing to take into account the standard error measurement, Florida’s law not only contradicts the test’s own design but also bars an essential part of a sentencing court’s inquiry into adaptive functioning.” Id. at 2001.

It was in light of Hall that the Second Circuit remanded Wilson’s case a second time. See Wilson, 571 Fed.Appx. at 19. However, the Circuit’s remand order did not indicate precisely how or even whether Hall affected this court’s original analysis of Wilson’s Atkins claim. Id. at 19-20. Accordingly, the court ordered the parties to submit additional briefing setting forth the pertinent issues from Hall and proposing what further steps the court should take pursuant to the remand order. (See Tr. of July 1, 2014, Proceedings (Dkt. 1504) at 5.) Wilson filed his briefing as a motion for reconsideration, along with six expert declarations. (Mot. for Recons. (“Def.’s Mot.”) (Dkt. 1505).) The Government submitted a response in opposition (Resp. in Opp’n (“Gov’t’s Resp.”) (Dkt. 1508)), and Wilson submitted a reply (Ltr. in Reply (“Def.’s Reply”) (Dkt. 1509)).

On April 28, 2015, the court ordered further briefing on the question of whether the 2013 publication — after the original Atkins hearing — of an updated version of the American Psychiatric Association’s (the “APA”) Diagnostic and Statistical Manual of Mental Disorders (5th ed. 2013) (the “DSM-V”), required the court to conduct additional factfinding with regard to Wilson’s Atkins claim. (Apr. 28, 2015, Order (Dkt. 1510).) Wilson filed a response requesting a hearing (Def.’s Not. in Resp. (Dkt. 1513)), and he submitted an additional expert declaration in support thereof (Def.’s Ltr.-Reply (Dkt. 1520)). The Government filed a response opposing a further hearing. (Gov’t’s Ltr.-Resp. (Dkt. 1519).)

On October 22, 2015, the court ordered the parties to further brief the following question: “In analyzing Wilson’s adaptive functioning, what additional evidence, if any, would the court need to consider, beyond that which is already in the record from the previous Atkins hearing?” (Oct. 22, 2015, Order (Dkt. 1522) at 2.) Wilson filed a .response (Def.’s Ltr.-Resp. (Dkt. 1524)), as did the Government (Gov’t’s PreTrial Mem. (Dkt. 1525)).

B. Issues Presented on Remand

As outlined below, the court has identified three main issues presented by the Second Circuit’s remand. First, the court addresses whether the intervening publication of the DSM-V fundamentally alters the legal standard or requires the court to re-open the Atkins hearing to conduct further factfinding. Second, the court must determine whether Hall’s treatment of IQ scores requires the court to reconsider its prong one analysis of Wilson’s intellectual functioning. Third, assuming Wilson demonstrates significantly subaverage intellectual functioning, the court must determine whether Wilson satisfies the remaining independent requirements of the legal standard for intellectual disability — namely, significant deficits in adaptive functioning and onset of the condition before the age of 18.

II. LEGAL STANDARD FOR INTELLECTUAL DISABILITY

In 1988, Congress enacted the FDPA, which provides that “a sentence of death shall not be carried out upon a person who is [intellectually disabled].” 18 U.S.C. § 3596(c). In 2002, the Supreme Court held in Atkins that the execution of intellectually disabled defendants violates the Eighth Amendment’s bar on cruel and unusual punishment. See Atkins, 536 U.S. at 321, 122 S.Ct. 2242; see also United States v. Davis, 611 F.Supp.2d 472, 473 (D.Md.2009) (noting that with Atkins, “the federal policy embodied in the [FDPA] became a constitutional imperative”).

In Wilson II, this court noted that neither the FDPA nor Atkins mandated a particular definition of intellectual disability, and that Atkins expressly left “to the States the task of developing appropriate ways to enforce the constitutional restriction upon their execution of sentences.” Id. at 337 (quoting Atkins, 536 U.S. at 317, 122 S.Ct. 2242). As this issue was a question of first impression in the Second Circuit, the court provided a lengthy discussion of the process by which it would identify the appropriate legal standard. See id.

The court first declared that it would consider New York law in determining the definition of intellectual disability, but that it also would rely heavily on the clinical definitions promulgated by the American Association of Intellectual and Developmental Disabilities (the “AAIDD”) and the APA, in keeping with the approach taken by most federal courts in Atkins cases. See id. at 338 (citing cases). The court emphasized, however, that clinical definitions inform, but do not dictate, the legal standard for intellectual disability. See id. at 339 (“The court will thus rely heavily upon clinical definitions and expert testimony to determine the definition of [intellectual disability] for capital punishment purposes, but, particularly where these definitions and testimony are ambiguous or conflicting ... it will apply its own judgment as to the ‘appropriate ways’ to enforce the ultimately legal prohibition on executing [intellectually disabled] offenders.” (emphasis in original) (quoting Atkins, 536 U.S. at 317, 122 S.Ct. 2242)).

The court then turned to the leading clinical sources and found that the definitions for intellectual disability set forth by the APA and the AAIDD were essentially identical. Id. at 341; see APA, Diagnostic and Statistical Manual of Mental Disorders (4th ed. 2000) (“DSM-IV”); AAIDD, Intellectual Disability: Definition, Classification, and Systems of Supports (11th ed. 2010) (“AAIDD 2010 Manual”). Considering those clinical standards, and in an approach consistent with other federal courts, the court held that the legal standard for intellectual disability required a person to satisfy three necessary elements: “(1) significantly subaverage intellectual functioning; (2) significant deficits in adaptive behavioral skills; and (3) onset of those limitations before the age of 18.” Wilson II, 922 F.Supp.2d at 343 (citing AAIDD 2010 Manual at 7, 27, 41; DSM-IV at 49; Taylor v. Quarterman, 498 F.3d 306, 307 (5th Cir.2007); United States v. Northington, No. 07-CR-550, 2012 WL 4024944, at *3 (E.D.Pa. Sept. 12, 2012); Davis, 611 FlSupp.2d at 475); see also United States v. Williams, 1 F.Supp.3d 1124, 1137-39 (D.Haw.2014) (citing Wilson II and adopting the same legal standard); United States v. Montgomery, No. 11-CR-20044 (JPM), 2014 WL 1516147, at *4-5 (W.D.Tenn. Jan. 28, 2014) (same).

In evaluating intellectual functioning specifically, the court determined that it would rely primarily on IQ scores, noting that “both the AAIDD and the APA define significantly subaverage intellectual functioning by reference to an IQ score approximately two standard deviations below the mean, or 70.” 922 F.Supp.2d at 344 (citing AAIDD 2010 Manual at 27; DSM-IV at 49). The court determined that it would apply one test-specific standard error measurement (“SEM”) to each score, id. at 347-49, resulting in a 68% confidence interval — the “range of scores within which one could be [68]% confident that a person’s true IQ score falls,” id. at 345. Next, the court declared that it would adjust Wilson’s scores based on the so-called “Flynn effect,” which takes into account a gradual upward trend in the population-wide average IQ score over time. Id. at 349-51. The court also decided that it would take into account the “practice effect” — that is, the expectation that an individual’s IQ score may improve over time as a result of familiarity with the particular test — but that it would not apply any particular point adjustment to Wilson’s scores on that basis. Id. at 353-54.

The court further held that while the standard for intellectual disability under the Eighth Amendment and the FDPA was a legal matter, the ultimate issue of whether Wilson was, in fact, intellectually disabled was “for the court to decide as a factual matter, ‘based upon all of the evidence and determinations of credibility.’” Id. at 343 (citing In re Briseno, 135 S.W.3d 1, 9 (Tex.Crim.App.2004)). Finally, the court held that on the issue of intellectual disability, Wilson would bear the burden of proof by a preponderance of the evidence. Id. at 343.

As explained below, these same general legal principles apply to Wilson today, with one critical caveat: While states and lower federal courts continue to bear the responsibility for establishing legal standards for intellectual disability, Hall establishes rules for the use of IQ scores in determining whether capital defendants meet those standards. Because the court’s past treatment of Wilson’s IQ scores differs from the approach mandated by Hall, the court must reconsider its original conclusion that Wilson is not intellectually disabled.

A. Effect of the DSM-V

1. Effect of the DSM-V on the Three-Prong Test for Intellectual Disability

Independent of Hall, Wilson argues that the DSM-V has fundamentally reconfigured the test for intellectual disability into a holistic inquiry of intellectual and adaptive functioning. (See Def.’s Mot. at 20.) While in Wilson II the court relied on the prior edition of the manual, the DSM-IV, Wilson maintains that the DSM-V represents “a paradigm shift in the [APAj’s conceptualization of intellectual disability and its diagnostic criteria,” and “emphatically underscores a shift away from any suggestion that IQ scores predominate and toward a concurrent assessment of both elements.” (Id.) Now, Wilson contends, “IQ scores are but one factor to be considered, in the exercise of clinical judgment, along with the full range of clinically relevant information, including, especially, adaptive functioning evidence, to determine whether a person has significant limitations in intellectual functioning.” (Id.) The court disagrees.

To be clear, the court has never suggested that IQ scores “predominate” in the overall analysis of intellectual disability. Rather, the court simply found that the first prong of the analysis — intellectual functioning — is “primarily evaluated using standardized tests that measure a person’s ‘Intelligence Quotient,’ or IQ.’” Wilson II, 922 F.Supp.2d at 343. This finding was consistent with federal case law and clinical authority. See United States v. Hardy, 762 F.Supp.2d 849, 876 (E.D.La.2010) (“The Court, in keeping with the views of the APA and the [AAIDD], has and will rely on Hardy’s IQ test score to determine whether he meets the first criterion of the definition of [intellectual disability].”); Thomas v. Allen, 614 F.Supp.2d 1257, 1264 (N.D.Ala.2009); AAIDD 2010 Manual at 31 (“Although far from perfect, intellectual functioning is currently best represented by IQ scores when they are obtained from appropriate, standardized and individually administered assessment instruments.”). Consequently, because significantly subav-erage intellectual functioning is one of the necessary elements of a finding of intellectual disability, the court found that it was unnecessary to consider adaptive functioning where it determined that Wilson could not satisfy the intellectual functioning prong based on his IQ scores.

Moreover, it is far from clear that the DSM-V constitutes the “paradigm shift” that Wilson claims it does on this matter. Most importantly, Hall — which did not fundamentally reshape the relationship between intellectual and adaptive functioning considerations — itself cited the DSM-V repeatedly in reaching its holding. See Hall, 134 S.Ct. at 1990, 1991, 1994, 2000, 2001. Yet Hall did not hold that courts always must assess evidence of adaptive functioning regardless of the defendant’s IQ test scores. As explained more fully infra Part II.B.l, Hall instead requires that courts consider adaptive functioning only where the margin of error surrounding a defendant’s IQ test score includes numbers 70 or below.

Wilson also has not shown that the DSM-V constitutes such a meaningful change from the DSM-IV that the legal standard for establishing intellectual disability under the FDPA must change accordingly. While Wilson proffers purported expert testimony suggesting that the DSM-V “represents a paradigm shift,” this testimony fails to explain exactly how the DSM-V is so different.

First, Wilson’s expert points out that while the DSM-IV described intellectual disability as “subaverage general intellectual functioning that is accompanied by significant limitations in adaptive functioning,” the DSM-V now describes it as “in-clud[ing] both intellectual and adaptive functioning deficits in conceptual, social, and practical domains.” (Decl. of Marc J. Tassé (“Tassé Decl.”) (Def.’s Mot., Ex. E (Dkt. 1505-5)) ¶ 31.) With respect to the FDPA, however, this appears to be a distinction without a difference. According to the DSM-V, a diagnosis of intellectual disability continues to require the following three criteria to be met: deficits in intellectual functioning, deficits in adaptive functioning, and onset of these deficits during the developmental period. DSM-V at 33. This is essentially the same understanding advanced in the DSM-IV and articulated by the Supreme Court in Hall.

Next, Wilson argues that this purported “paradigm shift” is underscored by the new manner in which the DSM-V distinguishes between levels of severity of intellectual disability. He proffers expert testimony stating that “[t]he various levels of severity [mild, moderate, severe, and profound] are defined on the basis of adaptive functioning, and not IQ scores, because it is adaptive functioning that determines the level of supports required.” (Def.’s Mot. at 20 (quoting Tassé Decl. ¶ 31).) But Wilson does not explain why the use of adaptive functioning evidence to determine the severity of an intellectual disability should affect the question whether a person is intellectually disabled in the first place. Moreover, while assessment of adaptive functioning apparently determines the level of support an intellectually disabled person may require in terms of social services, it does not follow that assessment of a defendant’s intellectual functioning should therefore be subsumed by adaptive functioning for the purpose of determining “whether imposition of a death sentence in a particular case would serve a valid peno-logical end.” Hall, 134 S.Ct. at 2006 (Alito, J., dissenting (“In a death-penalty case, intellectual functioning is important because of its correlation with the ability to understand the gravity of the crime and the purpose of the penalty, as well as the ability to resist a momentary impulse or the influence of others.”)).

Ultimately, the stark difference between psychological and penological goals explains why the determination of intellectual disability for the purpose of the FDPA is a legal, rather than a clinical, decision. See Wilson II, 922 F.Supp.2d at 356 (“[E]ven assuming that it is proper for psychologists to use a holistic approach when interpreting IQ scores in light of their clinical judgment, this does not mean that a court should meld the two prongs together when making a legal determination of who is ineligible for the death penalty.” (emphasis in original)). In Hall itself, the Court pointed out that while it relied substantially upon clinical approaches for guidance, it was the Court’s “independent assessment that an individual with an IQ test score ‘between 70 and 75 or lower,’ may show intellectual disability by presenting additional evidence regarding difficulties in adaptive functioning.” 134 S.Ct. at 2000. The Court explained:

In addition to the views of the States and the Court’s precedent, this determination is informed by the views of medical experts. These views do not dictate the Court’s decision, yet the Court does not disregard these informed assessments. It is the Court’s duty to interpret the Constitution, but it need not do so in isolation. The legal determination of intellectual disability is distinct from a medical diagnosis, but it is informed by the medical community’s diagnostic framework. Atkins itself points to the diagnostic criteria employed by psychiatric professionals. And the professional community’s teachings are of particular help in this case, where no alternative definition of intellectual disability is presented and where this Court and the States have placed substantial reliance on the expertise of the medical profession.

Id. (emphasis added) (internal citations omitted). Yet even as the Court in Hall placed substantial reliance on the DSM-V, the decision was grounded in a framework whereby the legal test for intellectual disability remained composed of three necessary and independent elements. Significantly, Wilson does not argue that the Supreme Court misunderstood or misinterpreted the DSM-V in Hall, and this court is bound by that decision. Accordingly, the court finds that the DSM-V does not affect the independent, three-prong legal framework for determining intellectual disability.

2. Effect of the DSM-V on the Definition of Adaptive Functioning

Although the court previously did not reach the issue of Wilson’s adaptive functioning, see Wilson II, 922 F.Supp.2d at 368, the court did cite the clinical definitions of adaptive functioning as set forth by the APA and the AAIDD, id. at 355. At the time, the APA described adaptive functioning as “how effectively individuals cope with common life demands and how well they meet the standards of personal independence expected of someone in their particular age group, sociocultural background, and community setting.” DSM-IV at 42. To satisfy prong two, the DSM-IV required deficits in at least two of ten skill areas: “communication, self-care, home living, social/interpersonal skills, use of community resources, self-direction, functional academic skills, work, leisure, health and safety.” Id. at 49. The AAIDD, on the other hand, defined (and continues to define) prong two broadly as “significant limitations ... in conceptual, social, and practical adaptive skills.” AAIDD 2010 Manual at 21. To meet this prong under the AAIDD definition, an individual must show deficits in one of these three general domains. Id. at 6.

Subsequent to the court’s decision in Wilson II, the APA updated the DSM and, in turn, its definition of adaptive functioning. The DSM-V definition now uses similar language to that of the AAIDD, framing adaptive functioning in terms of conceptual, social, and practical domains. DSM-V at 37-38.

Given the fact that the DSM-V was published after the 2012 Atkins hearing, the court initially was concerned that additional factfinding might be required in order to apply the new definition to Wilson’s case. Accordingly, the court twice ordered further briefing from the parties addressing the questions of whether the DSM-V’s adaptive functioning language represented a material change from the DSM-IV and whether the revision required the consideration of any additional evidence beyond that which was already included in the Atkins hearing record. (See Apr. 28, 2015, Order; Oct. 22, 2015, Order.) Specifically, the court was interested in whether the DSM-V represented a narrowing or broadening of the APA’s definition of adaptive functioning, such that certain evidence of an individual’s adaptive functioning that was not considered under a DSM-IV analysis might be relevant to a DSM-V analysis, and vice versa. If that had been the case, the court was prepared to re-open the Atkins hearing to consider such evidence. However, for the following reasons, the court has determined that the DSM-V does not mark such a substantive change to the clinical definition of adaptive functioning that a new hearing would be required.

First, although Wilson interprets the DSM-V as representing “a paradigm shift in the [APAJ’s conceptualization of intellectual disability and its diagnostic criteria,” (Def.’s Mot. at 2), he has not shown that a new hearing would allow him to present additional evidence of deficits in his adaptive functioning that was not presented in the initial Atkins hearing. Instead, a hearing would simply provide the parties’ experts with an opportunity to further explain their different interpretations of the DSM-V. As both parties have already submitted expert declarations explaining their respective interpretations, in-person testimony likely would consist of those experts simply repeating their arguments. Nor does either side suggest that the court’s adaptive functioning analysis would reach a different result today than in 2012. See Williams, 1 F.Supp.3d at 1152 (noting that two experts had testified prior to the publication of the AAIDD 2010 Manual and the DSM-V, but finding that “Defendant has presented no convincing evidence (if any) that these opinions would be different ... under newer clinical standards”). In fact, in his response to the court’s October 22, 2015, Order, Wilson declared that he had “already established the fact of his deficits in adaptive functioning on the basis of the existing record,” and that the court “need not take additional evidence on that factual question.” (Def.’s Ltr.-Resp. at 3.)

Second, even if the DSM-V did represent a material change from the DSM-IV, it would only serve to further harmonize the clinical standards of the APA and the AAIDD, minimizing any potential inconsistencies in the definitions which may have been present at the 2012 Atkins hearing. In fact, it appears to be a regular pattern that the APA updates its standards to track changes in the AAIDD’s definition. As the district court in Hardy explained,

‘[T]he three broad domains of adaptive behavior in [the AAIDD’s] definition represent a shift from the requirement ... that a person have limitations in at least 2 of the 10 specific skill areas listed in the [AAIDD’s] 1992 definition,’ which was the model for the approach ... used by the APA [in the DSM-IV]. ... The AAIDD moved away from that model .because ‘[t]he three broader domains of conceptual, social, and practical skills ... are more consistent with the structure of existing measures and with the body of research on adaptive behavior.’

762 F.Supp.2d at 879 (quoting American Association of Mental Retardation, Mental Retardation: Definition, Classification, and Systems of Supports (10th ed. 2002) at 73, 78)); see also McManus v. Neal, 779 F.3d 634, 654 n. 8 (7th Cir.2015) (“The DSM-V, like the AAIDD, now looks to the conceptual, social, and practical domains. The older list of skill areas has been subsumed into these categories.”); id. at 651 (characterizing the AAIDD and APA definitions of adaptive functioning as “essentially equivalent”).

Moreover, the fact that the DSM-IV definition of intellectual disability was also considered to be “essentially identical” to that of the AAIDD, see Wilson II, 922 F.Supp.2d at 341 (citing cases), further supports the court’s conclusion that the overall clinical standard has not changed significantly since the 2012 Atkins hearing. See Smith v. Ryan, 813 F.3d 1175, 1209-10, 2016 WL 454337, at *29 (9th Cir.2016), as corrected (Feb. 17, 2016) (“Although the same professional manuals cited in Atkins are no longer the most current versions, the same conclusion is equally likely with respect to the more recent editions.”); Chase v. State, 171 So.3d 463, 471 (Miss.2015) (“The [AAIDD and DSM-V definitions of intellectual disability] have not materially altered the diagnosis of intellectual disability [cited in Atkins] but have provided new terminology.”); Williams, 1 F.Supp.3d at 1146-47 (finding that, “in the end, the exact wording of the various standards makes little substantive difference,” and that “with the recent release of the [DSM-V] ... the Court need not decide which definition of prong two is preferable or correct, because the differences between them are mostly theoretical”).

Accordingly, the court sees no reason to hold a new hearing simply because the APA has updated its manual. Instead, in analyzing Wilson’s adaptive functioning, the court will rely on the evidence in the record from the 2012 Atkins hearing, the post-hearing briefing, and all submissions from the parties following the Second Circuit’s 2014 remand order. The court will apply the definitions of adaptive functioning set forth in the DSM-V and the AAIDD 2010 Manual, as well as those publications’ articulations of the standard for the second prong of a finding of intellectual disability. Because the court finds that the DSM-V is “essentially equivalent” to the DSM-IV and has “subsumed” the DSM-IV’s list of skill areas into the same three categories used by the AAIDD (the conceptual, social, and practical domains), see McManus, 779 F.3d at 654 n. 8, the court will interpret any testimony that references the DSM-IV in light of the DSM-V’s updated terminology.

B. Prong I: Intellectual Functioning

Hall presents the court with three specific issues that it must address in reconsidering whether Wilson has demonstrated significant deficits in intellectual functioning. First, the court responds to Wilson’s argument that, as with the DSM-V, Hall fundamentally reconfigures the relationship between the intellectual and adaptive functioning prongs of the test for intellectual disability. Second, the court describes Hall’s effect on the determination of which SEM and confidence interval to apply to Wilson’s IQ scores. Third, the court interprets Hall’s effect on the treatment of multiple, inconsistent IQ scores.

1. Relationship between Intellectual and Adaptive Functioning

Before Hall, it appeared clear that a finding of intellectual disability required a showing of deficits in both intellectual functioning and adaptive functioning. See Atkins, 536 U.S. at 318, 122 S.Ct. 2242 (“[C]linical definitions of [intellectual disability] require not only subaverage intellectual functioning, but also significant limitations in adaptive skills.” (emphasis added)). In other words, subaverage intellectual functioning and significant limitations in adaptive functioning were both necessary and independent elements; a defendant was required to prove both in order to demonstrate that he was intellectually disabled and, thus, ineligible for the death penalty. As a result, the court concluded in Wilson II that where a defendant failed to show an adequate deficit in intellectual functioning, it was not necessary to consider whether the defendant was also deficient in adaptive functioning. 922 F.Supp.2d at 357 (“Because the law is clear that [intellectual disability] contains three necessary elements, the court must determine if these elements are independently satisfied.”).

Wilson argues — as does the Hall dissent — that Hall merges what previously were separate and independent requirements into two factors that must simultaneously be considered. (Def.’s Mot. at 21 (arguing that this court’s “refusal to consider evidence of adaptive function, its treatment [of] the intellectual functioning and adaptive functioning elements as distinct and sequential, determined exclusively by IQ scores” was “squarely rejected in Hall.” (citing 134 S.Ct. at 2001 (“It is not sound to view a single factor as dispositive of a conjunctive and interrelated assessment.”))).) See Hall, 134 S.Ct. at 2007 (Mito, J., dissenting) (“[T]he Court establishes a standard that conflates what have long been understood to be two independent requirements for proving intellectual disability.”); id. at 2008 (“[T]he Court now holds that when a defendant’s IQ score is as high as 75, a court must ‘consider factors indicating whether the person has deficits in adaptive functioning.’ In other words, even when a defendant has failed to show that he meets the first prong of the well-accepted standard for intellectual disability ... evidence of the second prong ... can establish intellectual disability.” (citation omitted)). As a result, Wilson argues that courts must holistically consider evidence of deficits in both adaptive and intellectual functioning in determining whether a capital defendant is intellectually disabled under the FDPA. (Def.’s Mot. at 22.) However, neither Wilson’s nor the dissent’s conclusions are warranted by a careful reading of the Supreme Court’s decision in Hall.

In Hall, the Court held that “an individual with an IQ test score ‘between 70 and 75 or lower,’ may show intellectual disability by presenting additional evidence regarding difficulties in adaptive functioning.” 134 S.Ct. at 2000 (citing Atkins, 536 U.S. at 309 n. 5, 122 S.Ct. 2242). It is true that this language represents a change from Atkins. While Atkins left to the states the responsibility for establishing their own processes for determining whether a defendant was intellectually disabled, see 536 U.S. at 317, 122 S.Ct. 2242, after Hall, states may no longer implement a strict cut-off for defendants whose reported IQ test scores are 70 or higher. See Hall, 134 S.Ct. at 2001. Instead, courts are now required to take the SEM into account when evaluating IQ test scores. See id. As Wilson and the Hall dissent point out, these two aspects of Hall were not required by Atkins. See id. at 2003 (Alito, J., dissenting).

It is not true, however, that this holding fundamentally reconfigured the relationship between the first two prongs of the test for intellectual disability. Rather, Hall simply clarifies what constitutes sufficient evidence of a deficit in intellectual functioning. Since courts must now view an IQ test “score” as a range of scores derived from the SEM, the result of Hall is that a defendant with an IQ score of — for example — 71 (with a SEM of anything greater than 0.5 and a 95% confidence interval), is now deemed to have presented sufficient evidence of significantly subaverage intellectual functioning. See Hall, 134 S.Ct. at 2001 (“[W]hen a defendant’s IQ test score falls within the test’s acknowledged and inherent margin of error, the defendant must be able to present additional evidence of intellectual disability, including testimony regarding adaptive deficits.”).

By contrast, Hall does not stand for the proposition that courts must always examine evidence of deficits in adaptive functioning, regardless of the defendant’s intellectual functioning. While the majority used expansive language in portions of its opinion, see id. at 2001, the decision required an analysis of adaptive functioning only for defendants who receive scores for which the margin of error creates a range that includes 70 or below, see id. at 1996 (“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.”). Most importantly, the logic of the decision was limited to cases in which the defendant’s IQ score was only “somewhat higher than 70.” Id. at 1999. In these “borderline” cases, because “IQ test scores should be read not as a single fixed number but as a range,” and the confidence interval associated with a test score of 75 includes a score of 70 — the traditional benchmark for significantly subaverage intellectual functioning — the defendant’s IQ range would demonstrate a deficit in intellectual functioning. See id. at 1996 (noting that the SEM “allows clinicians to calculate a range within which one may say an individual’s true IQ score lies”). Since these defendants thus would have satisfied the first prong of the test, Hall merely requires that they be permitted to introduce evidence of deficits in adaptive functioning, as would any other capital defendant who satisfied prong one. Therefore, Hall clearly applies only to those defendants whose test results have a margin of error that includes a score of 70 or below.

Although Wilson seizes on particular language in Hall that suggests the decision should be construed more broadly, this effort is unpersuasive. Wilson focuses on a comment at the end of the decision, where the majority stated, “It is not sound to view a single factor as dispositive of a conjunctive and interrelated assessment.” Hall, 134 S.Ct. at 2001 (citing DSM-V at 37 (“[A] person with an IQ score above 70 may have such severe adaptive behavior problems ... that the person’s actual functioning is comparable to that of individuals with a lower IQ score.”)). However, this aside is not a necessary premise in the court’s holding, and therefore it must be construed as dicta.

In addition, the statement must be interpreted in the context in which it was written. Immediately prior to this remark, the Court articulated its holding that “when a defendant’s IQ test score falls within the test’s acknowledged and inherent margin of error, the defendant must be able to present additional evidence of intellectual disability, including testimony regarding adaptive deficits.” Id. Immediately following the Court’s comment, it explained that Florida’s statute, “as interpreted by its courts, misuses IQ score on its own terms; and this, in turn, bars consideration of evidence that must be considered in determining whether a defendant in a capital case has [an] intellectual disability.” Id. (emphasis added). Significantly, this language implies that it was the Florida court’s treatment of the IQ score as a fixed point which resulted in the error, not its failure to consider adaptive functioning regardless of IQ test score. In other words, this application of Florida’s statute was unconstitutional not because it failed to consider adaptive functioning as a general matter, but because it resulted in the failure to consider adaptive functioning specifically where the IQ score indicated the defendant had demonstrated a deficit in intellectual functioning. The Court did not say, however, that adaptive functioning must always be considered. Accordingly, this court will continue to apply the independent, three-prong test in its analysis of Wilson’s Atkins claim.

2. What SEM and Confidence Interval to Apply to a Defendant’s IQ Score

The most significant feature of Hall is its focus on the SEM and Florida’s failure to take measurement error into account when analyzing defendants’ intellectual functioning. Unfortunately, Hall does not provide clear guidance with respect to how lower courts should apply this concept in practice.

First, the Court did not indicate whether courts should apply the SEM associated with each individual test score, or a SEM of five across all test scores. On the one hand, the Court held that “when a defendant’s IQ test score falls within the test’s acknowledged and inherent margin of error, the defendant must be able to present additional evidence of intellectual disability.” 134 S.Ct. at 2001 (emphasis added). Given the Court’s observation that each test has a unique margin of error, see, e.g., id. at 1995 (noting that “[e]ach IQ test has a standard error of measurement,” which “is a statistical fact, a reflection of the inherent imprecision of the test itself’ (internal citation and quotation marks omitted)), this language suggests that lower courts are to apply the specific SEM associated with that particular test, which is what this court did in Wilson II. See 922 F.Supp.2d at 347. On the other hand, given the Court’s apparent holding that “an individual with an IQ test score ‘between 70 and 75 or lower’ may show intellectual disability by presenting additional evidence regarding difficulties in adaptive functioning,” Hall could also be read to require that lower courts apply one blanket SEM of plus or minus five, regardless of the test-specific SEM. 134 S.Ct. at 2000; see also id. at 2010 (Alito, J., dissenting).

Second, the Court did not provide clear guidance on the appropriate confidence level lower courts should apply to this analysis. Assuming courts should apply the test-specific SEM — instead of a blanket five-point margin of error — Hall does not explicitly state whether courts should apply one or two SEMs in constructing the range of possible IQ test scores. In other words, the Court does not indicate whether lower courts must utilize a 68% confidence interval (defined as IQ test score ± one SEM) or a 95% confidence interval (defined as IQ test score ± two SEMs) to determine the defendant’s IQ score range. Although the Court consistently referred to the use of “the SEM” in the singular, see, e.g., id. at 1995 (“each separate score must be assessed using the SEM”), 1999 (“clinical definitions have long included the SEM”), 2000 (“By failing to take into account the SEM and setting a strict cutoff at 70, Florida goes against the unanimous professional consensus.” (citation and internal quotation marks omitted)), the decision nonetheless contains language which explicitly suggests that application of a five-point margin would result in a 95% confidence interval (i.e., two SEMs), see id. at 1995 (“A score of 71, for instance is generally considered to reflect a range between 66 and 76 with 95% confidence and a range of 68.5 and 73.5 with 68% confidence.”); id. (“For example, the average SEM for the WAIS-IV is 2.16 IQ test points and the average SEM for the Stan-fordBinet 5 is 2.30 IQ test points.” (citing amicus brief of the APA)). Yet if Hall really meant that lower courts should apply a 95% confidence interval, it is unclear why the Court would repeatedly emphasize a five-point margin, when — if the average SEM is between 2.16 and 2.30 — the use of a five-point range would be over-inclusive in some cases (where two SEMs is less than five points) and under-inclusive in others (where two SEMs is greater than five points).

The Hall dissent anticipated that the majority’s decision would “surely confuse States attempting to comply with its opinion,” especially in this regard. See id. at 2010. The dissent explained:

First, the Court unjustifiably assumes a blanket (or very common) error measurement of 5. That assumption gives rise to the Court’s holding that a defendant must be permitted to introduce additional evidence when IQ tests reveal an IQ as high as 75. SEMs, however, vary by IQ test and test-taker, and there is no reason to assume a SEM of 5 points; indeed, it appears that the SEM is generally “estimated to be three to five points” for well-standardized IQ tests. And we know that the SEM for Hall’s. most recent IQ test was 2.16 — less than half of the Court’s estimate of 5. Relatedly, the Court misreads the authorities on which it relies to establish this cutoff IQ score of 75. It is true that certain professional organizations have advocated a cutoff of 75 and that Atkins cited those organizations’ cutoff. But the Court overlooks a critical fact: Those organizations endorsed a 75 IQ cutoff based on their express understanding that “one standard error of measurement [SEM]” is “three to five points for well-standardized” IQ tests. In other words, the number 75 was relevant only to the extent that a single SEM was “estimated” to be as high as 5 points. Here, by contrast, we know that the SEM for Hall’s latest IQ test was less than half of that estimate; there is no relevance to the number 75 in this case. To blindly import a five-point margin of error when we know as a matter of fact that the relevant SEM is 2.16 amounts to requiring consideration of more than two SEMs — an approach that finds no support in Atkins or anywhere else. Because of these factual errors and ambiguities, it is unclear to me whether the Court concludes that a defendant is constitutionally entitled to introduce non-test evidence of intellectual disability (1) whenever his score is 75 or lower, on the mistaken understanding that the SEM for most tests is 5; (2) when the [68]% confidence interval (using one SEM) includes a score of 70; or (3) when the 95% confidence interval (using two SEMs) includes a score of 70. In my view, none of these approaches is defensible.

An approach tied to a fixed score of 75 can be dismissed out of hand because, as discussed, every test has a different SEM.

The other two approaches would require that a defendant be permitted to submit additional evidence when his IQ is above 70 so long as the [68]% or 95% confidence interval (using one SEM or two SEMs, respectively) includes a score of 70, but there is no foundation for this in our Eighth Amendment case law. As Hall concedes, the Eighth Amendment permits States to assign to a defendant the burden of establishing intellectual disability by at least a preponderance of the evidence. In- other words, a defendant can be required to prove that the probability of a 70 or sub-70 IQ is greater than 50%. Under the Court’s approach, by contrast, a defendant could prove significantly subaverage intellectual functioning by showing simply that the probability of a “true” IQ of 70 or below is as little as [16]% (under a one-SEM rule) or 2.5% (under a two-SEM rule). This totally transforms the allocation and nature of the burden of proof.

Id. at 2010-ll(Alito, J., dissenting) (internal citations omitted).

Notwithstanding the validity of the dissent’s critique, this court must approach the task of applying Hall in light of these apparent contradictions. Read .literally, Hall may be interpreted as requiring lower courts to apply a strict IQ cutoff at 75. See id. at 1996 (“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.”). As the dissent points out, however, a blanket cutoff at 75 should be “dismissed out of hand,” because “every test has a different SEM,” id. at 2011 (Alito, J., dissenting), a fact highlighted by the majority itself, see id. at 1995. Moreover, such an approach might run counter to Hall itself. In situations where a given test’s SEM is greater than five, a blanket cutoff at 75 would run afoul of Hall’s requirement to apply the SEM.

But the question of whether the court should apply a 68% or 95% confidence interval is particularly vexing, as it has yet to be explicitly decided by any federal court, and it has significant implications in Wilson’s case in particular. As the court noted in Wilson II, application of the 68% confidence interval results in only one test for which Wilson’s IQ score range falls to 70 or below, see 922 F.Supp.2d at 359, and the court previously expressed a belief that this test (the December 5, 1994, test conducted by Dr. Nagler) was an outlier, see id. at 362, 367-68. If the court were to apply a 95% confidence interval, however, two tests — other than the Nagler score— would reflect a range of scores that fall to 70 or below, including one test before Wilson’s 18th birthday. See id. at 358 (showing that the bottom end of the 95% confidence interval for the administration of a test by Dr. Aranoff on October 27, 1993, was 69.98). After Hall, the presence of even one score at or below 70 is sufficient to show significant subaverage intellectual functioning and, accordingly, require consideration of evidence of adaptive functioning. (See infra Part II.B.3.)

As a result, the appropriate course of action in Wilson’s case effectively turns on the question of whether courts should apply one or two test-specific SEMs to a defendant’s IQ test score in determining the appropriate range. Although the court previously determined that a 68% confidence interval was more appropriate in.the Atkins context, 922 F.Supp.2d at 347-48, the most coherent interpretation of Hall requires the court to apply the larger, 95% confidence interval, derived by adding to and subtracting from each of Wilson’s IQ scores two test-specific SEMs. By indicating that the margin for measurement error was “generally” plus or minus five points, based on an average SEM of 2.16 or 2.30— depending on the test — the Supreme Court all but explicitly stated that lower courts should apply two SEMs in conducting this analysis. See Hall, 134 S.Ct. at 1995 (“A score of 71, for instance, is generally considered to reflect a range between 66 and 76 with 95% confidence and a range of 68.5 and 73.5 with 68% confidence.”). In fact, it is unclear why the Court would include a discussion of the 95% confidence interval if it reflected an unnecessarily cautious approach.

Moreover, the general tone of the Supreme Court’s decision strongly suggests that courts should not apply narrow margins of error when assessing intellectual functioning for the purpose of determining eligibility for the death penalty. See id. at 2000 (“An IQ score is an approximation, not a final and infallible assessment of intellectual functioning.”); id at 2001 (“Intellectual disability is a condition, not a number. Courts must recognize, as does the medical community, that the IQ test is imprecise. This is not to say that an IQ test score is unhelpful. It is of considerable significance, as the medical community recognizes. But in using these scores to assess a defendant’s eligibility for the death penalty, a State must afford these test scores the same studied skepticism that those who design and use the tests do, and understand that an IQ test score represents a range rather than a fixed number.” (internal citations omitted)); id. at 1990 (holding that Florida’s “rigid rule ... creates an unacceptable risk that person’s with intellectual disability will be executed”). While this reading does not require lower courts to examine evidence of a defendant’s adaptive functioning in every ease, it suggests that in close cases such as this, courts should resolve uncertainty in favor of defendants. The court finds that the application of a two-SEM, 95% confidence interval reflects an approach most in keeping with this directive.

3. Treatment of Multiple Test Results

Hall does not provide explicit guidance with respect to how courts should treat multiple IQ test results, some of which permit a finding of significantly subaver-age intellectual functioning and some of which do not. In particular, the Sumpreme Court was silent regarding the treatment of possible outliers and whether lower courts should compute averages. At its most explicit, Hall provides that “[e]ven when a person has taken multiple tests, each separate score must be assessed using the SEM, and the analysis of multiple IQ scores .jointly is a complicated endeav- or. Id. at 1995 (emphasis added) (citing Schneider, Principles of Assessment of Aptitude and Achievement, in The Oxford Handbook of Child Psychological Assessment 286, 289-291, 318 (D. Saklofske, C. Reynolds, V. Schwean, eds. 2013)).

Notwithstanding the lack of clear guidance on this issue, the facts in Hall require lower courts to consider evidence of adaptive functioning if even one valid IQ test score generates a range that falls to 70 or below. In Hall, the petitioner’s valid IQ test scores were 71, 72, 73, and 80. Id. at 2007 n. 9 (Alito, J., dissenting). Nonetheless, in concluding that Florida’s statute was unconstitutional, the Court focused on the fact that the statute would permit execution of a defendant whose score was as low as 71. Id. at 1992, 1995, 2001 (“Florida seeks to execute a man because he scored a 71 instead of 70 on an IQ test.”); see also id. at 2007 (Alito, J., dissenting) (“[0]ne would get the impression from reading the Court’s opinion that Hall introduced only one test score (of 71).”). Although Hall had consistently achieved IQ test scores above 70, including one score as high as 80, this did not change the Court’s analysis. See id. at 1995-96 (“[B]ecause the test itself may be flawed, or administered in a consistently flawed manner, multiple examinations may result in repeated similar scores, so that even a consistent score is not conclusive evidence of intellectual functioning.”); see also id. at 2011 (Alito, J., dissenting) (“The Court never explains why its criticisms of the uncertainty resulting from the use of a single IQ score apply when a defendant consistently scores above 70 on multiple tests. Contrary to the Court’s evident assumption, the well-accepted view is that multiple consistent scores establish a much higher degree of confidence.” (emphasis in original)).

Thus, the court interprets Hall to require a prong 2 analysis if any IQ test, evaluated in the context of a 95% interval, reflects a range falling to 70 or below.

C. Prong II: Adaptive Functioning

As explained above, the APA defines adaptive functioning in terms of three broad domains:

The conceptual (academic) domain involves competence in memory, language, reading, writing, math reasoning, acquisition of practical knowledge, problem solving, and judgment in novel situations, among others. The social domain involves awareness of others’ thoughts, feelings, and experiences, empathy, interpersonal communication skills; friendship abilities; and social judgment, among others. The practical domain involves learning and self-management across life settings, including personal care, job responsibilities, money management, recreation, self-management of behavior, and school and work task organization, among others.

DSM-V at 37-38. The AAIDD, similarly, defines prong two as “significant limitations ... in conceptual, social, and practical skills.” AAID 2010 Manual at 21. To meet prong two, the DSM-V states that a person’s adaptive functioning in at least one of these three domains must be “sufficiently impaired that ongoing support is needed in order for the person to perform adequately in one of more life settings at school, at work, at home, or in the community.” DSM-V at 38. Moreover, “the deficits in adaptive functioning must be directly related to the intellectual impairments described in [prong one].” Id.

In analyzing Wilson’s adaptive functioning, the court will also look to examples from case law where courts have reached prong two for purposes of resolving Atkins claims. See, e.g., Williams, 1 F.Supp.3d at 1145-48, 1161-67; United States v. Salad, 959 F.Supp.2d 865, 878 (E.D.Va.2013) (“Prong two generally requires a more expansive investigation of a defendant’s life history and skill levels than could be fully evaluated through use of a normed instrument.”); Davis, 611 F.Supp.2d at 491 (describing the prong two analysis as “amorphous”). Although some of these cases pre-date the DSM-V, the court finds their interpretations of the AAIDD standard particularly helpful, as the DSM-V now mirrors that terminology. For example, Salad summarizes the AAIDD framework as follows:

The AAIDD Manual provides several important guidelines for analyzing adaptive behavior. First, the analysis is ' often retrospective, in that it examines past behavior for evidence of conformity or non-conformity to the baseline standards for the subject’s age and background. AAIDD [2010] Manual at 46; see also Hardy, 762 F.Supp.2d at 881 (noting that, in the context of an Atkins claim[ ], the analysis is always retrospective). Second, in the absence of standardized measurements, analysts should examine multiple sources of information for “convergence”; exercise “reasonable caution” in resolving conflicting reports; and avoid drawing conclusions from isolated performances. AAIDD [2010] Manual at 48. That is, an evaluation should not rely primarily on an individual’s self-report of his skill level, but rather should rely on information gathered from third parties who are “very familiar with the person and have known him/her for some time and have had the opportunity to observe the person function across community settings and times.” Id. at 47. Third, the analysis should focus on average ability, not peak functioning. Id. (describing this broader focus as a “critical distinction” between prongs one and two). And finally, clinicians should be mindful that subjects with mild intellectual disability present a complex picture of strengths and weaknesses, and analysts should not evaluate a subject’s performance based on inaccurate stereotypes of disabled individuals. See id. at 7 (“[Limitations often coexist with strengths.”).

959 F.Supp.2d at 878.

As with the prong one analysis, however, the court is faced with several specific issues that it must address in analyzing Wilson’s adaptive functioning. First, the court describes the weight that should be given to results from standardized measures of adaptive functioning administered by the Government’s and Wilson’s experts. Second, the court addresses the probative value of adaptive functioning evidence that is derived from criminal and prison records. Finally, the court address whether prong two requires proof that a defendant’s adaptive deficits are caused by intellectual disability, as opposed to other disorders or disabilities.

1. Importance of Standardized Measures of Adaptive Functioning

Although not a formal component of the diagnostic criteria in either the DSM-Y or the AAIDD Manual, both standards direct clinicians to use standardized measures of adaptive functioning when possible. See DSM-V at 37 (“Adaptive functioning is assessed using both clinical evaluation and individualized, culturally appropriate, psy-chometrically sound measures.”); AAIDD 2010 Manual at 43 (“[Significant limitations in adaptive behavior should be established through the use of standardized measures normed on the general population[.]”). The AAIDD cautions, however, that “clinicians must recognize that adaptive behavior instruments are imperfect measures of personal competence that distinguish persons with and without ID as they face the everyday demands of life.” AAIDD 2010 Manual at 51.

Federal courts have been reluctant to rely heavily on such tests, particularly in the Atkins context where they often are based on retrospective recollections of an individual’s youth. In Hardy, for example, the district court noted that “the selection of the tests used to assess adaptive behavior, the persons selected as informants, the conduct of the interviews, and the ultimate interpretation of the tests’ results are a good deal more dependent on subjective clinical judgment than the assessment of IQ.” 762 F.Supp.2d at 88