Appeal from the Order entered on 04/15/2010 (Amended on 05/13/2010) in the Court of Common Pleas, Criminal Division, Allegheny County at No. CP-02-CR-0001876-2000.
The opinion of the court was delivered by: Justice Eakin
CASTILLE, C.J., SAYLOR, EAKIN, BAER, TODD, MCCAFFERY, ORIE MELVIN, J.J.
SUBMITTED: September 20, 2011
OPINION MR. JUSTICE EAKIN
The Commonwealth appeals from the order of the Court of Common Pleas of Allegheny County granting appellee's Post-Conviction Relief Act (PCRA)*fn1 petition and vacating his sentence of death on the basis that appellee demonstrated, by a preponderance of the evidence, that he is mentally retarded. As we find the PCRA court's factual findings are supported by substantial evidence, and its legal conclusions drawn therefrom are free from error, we affirm.
A jury convicted appellee of first degree murder*fn2 and abuse of a corpse*fn3 for stabbing his wife, Frances Williams, to death.*fn4 At the penalty phase, the jury found one aggravating circumstance*fn5 outweighed two mitigating circumstances.*fn6 Consequently, appellee was sentenced to death for murder, see id., Â§ 9711(c)(1)(iv), and a consecutive term of one to two years imprisonment for abuse of a corpse. After the trial court denied appellee's post-sentence motion, he appealed to this Court.
On direct appeal, appellee argued the imposition of the death penalty amounted to cruel and unusual punishment in violation of the United States Supreme Court's prohibition against the execution of the mentally retarded. See Atkins v. Virginia, 536 U.S. 304, 321 (2002).*fn7 We held, because the trial record was devoid of evidence pertaining to appellee's mental retardation and no standard for classifying a defendant as mentally retarded had been established for the purpose of analyzing Atkins claims in Pennsylvania, appellee's claim was best suited for collateral review. See 42 Pa.C.S. Â§ 9543(a)(2)(vi); Williams, at 448-49 (citing Commonwealth v. Mitchell, 839 A.2d 202, 209, 211 (Pa. 2003)). Finding appellee's remaining claims meritless, we affirmed his death sentence. Id., at 449.
Appellee received new counsel and filed a PCRA petition, which was subsequently amended. The PCRA court held an evidentiary hearing, limited to appellee's Atkins claim, and deferred his remaining issues pending the claim's resolution. PCRA Court Opinion, 4/15/10, at 3, 10-11. The court heard expert testimony presented by both the Commonwealth and appellee during the hearing.
Appellee also presented testimony from several lay witnesses. Consequently, the PCRA court determined appellee proved, by a preponderance of the evidence, he was mentally retarded. Id., at 11-12. Accordingly, the court granted the portion of appellee's amended petition seeking to vacate the death sentence, and imposed a sentence of life imprisonment. Id., at 12.
The Commonwealth appealed to this Court, limited to the issue of "[w]hether the PCRA court erred by concluding that appellee is mentally retarded as defined under Atkins v. Virginia, 536 U.S. 304 (2002)[,] and Commonwealth v. Miller, 585 Pa. 144, 888 A.2d 624 (2005), where the record as a whole contains abundant evidence that appellee does not have significant adaptive deficits[.]" Brief of Appellant, at 4.
Our standard of review of the PCRA court's determination regarding whether a petitioner is mentally retarded is a mixed question of law and fact, for which the standard of review is as follows:
A question involving whether a petitioner fits the definition of mental retardation is fact intensive as it will primarily be based upon the testimony of experts and involve multiple credibility determinations. Accordingly, our standard of review is whether the factual findings are supported by substantial evidence and whether the legal conclusion drawn therefrom is clearly erroneous. We choose this highly deferential standard because the court that finds the facts will know them better than the reviewing court will, and so its application of the law to the facts is likely to be more accurate.
Commonwealth v. Crawley, 924 A.2d 612, 616 (Pa. 2007) (citations and quotation omitted).
To obtain relief on an Atkins claim, the defendant must show, by a preponderance of the evidence, see id., at 616, he is mentally retarded as defined by the American Psychiatric Association (APA) or the American Association of Mental Retardation (AAMR).*fn8 Miller, at 626-27.*fn9
The AAMR defines mental retardation as a "disability characterized by significant limitations both in intellectual functioning and in adaptive behavior as expressed in the conceptual, social, and practical adaptive skills." Mental Retardation[: Definition, Classifications, and Systems of Supports (10th ed. 2002) (Mental Retardation)], at 1. The American Psychiatric Association defines mental retardation as "significantly subaverage intellectual functioning (an IQ of approximately 70 or below) with onset before age 18 years and concurrent deficits or impairments in adaptive functioning." [Diagnostic and Statistical Manual of Mental Disorders (4th ed. 1992) (DSM-IV),] at 37. Thus, . both definitions of mental retardation incorporate three concepts: 1) limited intellectual functioning; 2) significant adaptive limitations; and 3) age of onset.
Id., at 629-30 (footnote omitted) (emphasis added); see Crawley, at 614-15 (reaffirming Miller's standard). Accordingly, a defendant may establish mental retardation under either the AAMR or APA/DSM-IV classification systems so long as he proves by a preponderance of the evidence he has limited or subaverage intellectual functioning, significant adaptive limitations, and the onset of his subaverage intellectual functioning occurred before he was 18 years old.
The best representation of limited intellectual functioning is an individual's IQ score. Miller, at 630 (citing Mental Retardation, at 14, 57; DSM-IV, at 39). Considered within the limits of subaverage intellectual functioning is the standard error of measurement (SEM) for the specific assessment instruments used, which is estimated to be three to five points for well-standardized measures of general intellectual functioning. Id. Thus, a limited intellectual capability is commonly ascribed to an individual who tests within the SEM of the subaverage intellectual functioning range; its upper limit is 75 on the Wechsler scales. Id. (citing Mental Retardation, at 57-58; DSM-IV, at 39).
Although an individual's IQ score is the primary measurement for limited intellectual functioning, because the interaction between limited intellectual functioning and deficiencies in adaptive skills is necessary to establish mental retardation, a sufficiently high IQ score, in itself, will not bar a court from finding an individual is mentally retarded. Id., at 630-31. Nor will a low IQ score in itself categorize a person as mentally retarded. Id. For instance, an individual with an IQ score between 71 and 75 must have major deficiencies in adaptive behavior, whereas an individual with an IQ score lower than 70 must also be significantly deficient in adaptive behavior to be found mentally retarded. Id.
As pertaining to the second prong, adaptive behavior is defined as "the collection of conceptual, social, and practical skills that have been learned by people in order to function in their everyday lives, and limitations on adaptive behavior are reflected by difficulties adjusting to ordinary demands made in daily life." Id., at 630 (citing Mental Retardation, at 73; DSM-IV, at 40) (footnote omitted). "[P]erformance that is at least two standard deviations below the mean of either (a) one of the following three types of adaptive behavior: conceptual, social, or practical, or (b) an overall score on a standardized measure of conceptual, social and practical skills" constitutes significant limitations in adaptive functioning as defined by the AAMR. Id., at 630-31 (citing Mental Retardation, at ...