concurring in part and dissenting in part.
I respectfully dissent from Part II of the majority’s opinion, as I would grant Bowling permission to file a second or successive habeas corpus petition and issue a stay of execution pending final determination of his mental retardation claim.
Bowling has filed with this court an application to file a second or successive ha-beas corpus petition pursuant to 28 U.S.C. § 2244 and a petition requesting a stay of execution pending final determination of his mental retardation claim. To obtain this court’s permission to file a second or successive federal habeas corpus petition, the applicant must make a prima facie showing that the application satisfies the statutory requirements. 28 U.S.C. § 2244(b)(3)(C); In re Green, 144 F.3d 384, 388 (6th Cir.1998). A prima facie showing requires the applicant to set forth “sufficient allegations of fact together with some documentation that would ‘warrant a fuller exploration in the district court.’ ” In re Lott, 366 F.3d 431, 433 (6th Cir.2004) (quoting Bennett v. United States, 119 F.3d 468, 469 (7th Cir.1997)). I conclude that Bowling has made such a showing.
Although the Supreme Court held in Atkins v. Virginia, 536 U.S. 304, 122 S.Ct. 2242, 153 L.Ed.2d 335 (2002), that the execution of mentally retarded persons violates the Eighth Amendment, the Court *441did not explicitly define which persons qualify as mentally retarded under the Eighth Amendment, rather “leaving] to the State[s] the task of developing appropriate ways to enforce the constitutional restriction upon [their] execution of sentences.” Id. at 317, 122 S.Ct. 2242 (quoting Ford v. Wainwright, 477 U.S. 399, 405, 416-17, 106 S.Ct. 2595, 91 L.Ed.2d 335 (1986)) (second and third alterations in Atkins ). Twelve years prior to the Supreme Court’s decision in Atkins, the Commonwealth of Kentucky by statute abolished the death penalty for “seriously mentally retarded defendants],” i.e., persons “with significant subaverage intellectual functioning existing concurrently with substantial deficits in adaptive behavior and manifested during the developmental period.” Ky. Rev. Stat. §§ 532.130, 532.140. However, until Bowling’s appeal, judicial review of Kentucky’s mental-retardation statute had been quite circumscribed.1
In Bowling v. Commonwealth, 163 S.W.3d 361 (Ky.2005), the Kentucky Supreme Court concluded that Bowling was “not entitled to relief from his death sentence .... ” Id. at 366. Specifically, the court ruled that, although Atkins applies retroactively with respect to persons tried before Kentucky enacted its statutory ban on execution of mentally retarded persons, see id. at 371, 122 S.Ct. 2242, Bowling waived his mental-retardation claim because he was tried after the effective date of the Kentucky mental-retardation statute but had chosen not to raise the issue at trial. See id. at 372, 122 S.Ct. 2242. The court went on to state, though, that if Bowling could prove that he was mentally retarded, he would be actually innocent of the death penalty, and thus the “miscarriage of justice” exception to procedural default would apply. See id. at 372-73, 122 S.Ct. 2242.
Ultimately, the court declined to grant Bowling’s request for an evidentiary hearing because Bowling had failed to make a prima facie showing that he was mentally retarded under Kentucky law. See id. at 384 (“We hold that to be entitled to an evidentiary hearing on a claim of entitlement to the mental retardation exemption provided by KRS 532.140(1), a defendant must produce some evidence creating a doubt as to whether he is mentally retarded.”). The court determined that Kentucky Revised Statute § 532.130 mandates that a defendant have “an intelligence quotient (I.Q.) of seventy (70) or below,” but that the lowest IQ score Bowling had ever received was a 79. See id. The court *442further noted that, although there was some confusion whether Bowling received a 74 or an 84 on a 1966 IQ examination, “the relevancy of an IQ score of 74 at age thirteen would be clearly outweighed by Appellant’s IQ scores of 79 measured five months later, and 86 and 87 measured twenty-four years later and in the same time frame as the offenses and the trial.” Id. at 384 n. 37 (“If a trial court found otherwise, we would deem that finding to be clearly erroneous.”). The court also ruled that Kentucky’s statutory framework for adjudicating mental-retardation claims complies with Atkins, rejecting Bowling’s arguments that, inter alia, the Kentucky statutes define only severe mental retardation and that an IQ ceiling of 70 fails to account for margins of error in IQ tests and for increases in IQ scores as a person ages. See id. at 376-77.
Justice Keller, joined by Justice Graves, filed a dissenting opinion. First, Justice Keller stated that Atkins claims should not be deemed waived when a defendant fails to comply with Kentucky’s statutory requirement that mental-retardation issues be raised prior to trial, given that the Eighth Amendment claim arises only after conviction and that society has an independent interest in mentally retarded persons not being executed, which the defendant cannot waive. See id. at 385-86 (Keller, J., dissenting). Justice Keller also expressed his belief that Bowling had presented “sufficient [evidence] to create a doubt as to his mental condition,” noting that the record was ambiguous as to whether Bowling had received a 74 or an 84 on his November 1966 IQ exam and that it was the province of the trial court to resolve this factual issue in the first instance. See id. at 387 (Keller, J., dissenting). Justice Keller further noted that the Kentucky statute required an IQ of 70 or below, not an IQ score of 70 or below, and thus a judge should make an independent determination of a defendant’s IQ based on the entirety of the evidentiary record (taking into account such matters as margins-of-error and age-based scoring patterns) rather than depending strictly on an examination score. See id. at 388 (Keller, J., dissenting).
After reviewing the Kentucky Supreme Court’s decision and the parties’ briefing, I believe that Bowling has made a sufficient showing to obtain leave to file a second or successive habeas petition. The Kentucky Supreme Court’s rejection of Bowling’s mental retardation claim rested exclusively on the fact that Bowling had not presented any evidence that he had ever received an IQ test score of 70 or below. See id. at 384. However, there appears to be considerable evidence that irrebuttable IQ ceilings are inconsistent with current generally-accepted clinical definitions of mental retardation and that any IQ thresholds that are used should take into account factors, such as a test’s margin of error, that impact the accuracy of a particular test score.2 As then-California Supreme Court Justice Janice Rogers Brown explained in In re Hawthorne, 35 Cal.4th 40, *44324 Cal.Rptr.3d 189, 105 P.3d 552, 557-58 (2005):
With respect to the intellectual prong of [California’s mental retardation statute], respondent Attorney General urges the court to adopt an IQ of 70 as the upper limit for making a prima facie showing. We decline to do so for several reasons: First, unlike some states, the California Legislature has chosen not to include a numerical IQ score as part of the definition of mentally retarded.... Moreover, statutes referencing a numerical IQ generally provide that a defendant is presumptively mentally retarded at or below that level, rather than-as respondent impliedly argues-that a defendant is presumptively not mentally retarded above it. Second, a fixed cutoff is inconsistent with established clinical definitions and fails to recognize that significantly subaverage intellectual functioning may be established by means other than IQ testing. Experts also agree that an IQ score below 70 may be anomalous as to an individual’s intellectual functioning and not indicative of mental impairment. (See Am. Psychiatric Assn., Diagnostic and Statistical Manual of Mental Disorders (4th ed.2000) pp. 41-42.) Finally, IQ test scores are insufficiently precise to utilize a fixed cutoff in this context. {See id. at p. 41 [indicating IQ scores are considered to have a five-point measurement error]; AAMR, Mental Retardation: Definition, Classification, and Systems of Support (10th ed.2002) p. 57; Am. Assn. of Mental Deficiency, Classification in Mental Retardation (8th ed.1983) p. 11.)
(emphasis added, citations and footnote omitted); see also State v. Lott, 97 Ohio St.3d 303, 779 N.E.2d 1011, 1014 (2002) (“While IQ tests are one of the many factors that need to be considered, they alone are not sufficient to make a final determination on this issue. We hold that there is a rebuttable presumption that a defendant is not mentally retarded if his or her IQ is above 70.”); cf. Ford v. Wainwright, 477 U.S. 399, 417, 106 S.Ct. 2595, 91 L.Ed.2d 335 (1986) (“[T]he lodestar of any effort to devise a procedure must be the overriding dual imperative of providing redress for those with substantial claims and of encouraging accuracy in the fact-finding determination. The stakes are high, and the ‘evidence’ will always be imprecise.”).3
*444While it is true that Atkins vests states with the primary responsibility for defining mental retardation, states are not wholly unfettered in this process. Rather, states must adopt mental-retardation definitions and procedures for ascertaining a defendant’s mental capacity that are in accordance with the Eighth Amendment’s goals and principles. Thus, I would grant Bowling leave to fíle a second or successive habeas petition so that the district court and this court can consider whether Kentucky’s definition of mental retardation and its procedures for evaluating such a claim encompass the whole “range of mentally retarded offenders about whom there is a national consensus,” Atkins, 536 U.S. at 317, 122 S.Ct. 2242, and if not, whether Bowling qualifies as mentally retarded when all of the record evidence (not simply his IQ scores) is considered.
With respect to Bowling’s motion for a stay of execution, 28 U.S.C. § 2251 provides that:
A justice or judge of the United States before whom a habeas corpus proceeding is pending, may, before final judgment or after final judgment of discharge, or pending appeal, stay any proceeding against the person detained in any State court or by or under the authority of any State for any matter involved in the habeas corpus proceeding.
After the granting of such a stay, any such proceeding in any State court or by or under the authority of any State shall be void. If no stay is granted, any such proceeding shall be as valid as if no habeas corpus proceedings or appeal were pending.
Bowling has filed an application with this court seeking permission to file a second or successive habeas corpus petition asserting that his execution would violate the Eighth Amendment, and thus a habeas corpus proceeding is pending for purposes of § 2251. Cf. McFarland v. Scott, 512 U.S. 849, 859, 114 S.Ct. 2568, 129 L.Ed.2d 666 (1994) (“[A] capital defendant may invoke this right to a counseled federal habe-as corpus proceeding by filing a motion requesting the appointment of habeas counsel, and ... a district court has jurisdiction to enter a stay of execution where necessary to give effect to that statutory right.”). Thus, in order to ensure that Bowling’s Eighth Amendment claim can be heard by a federal court before he is executed, I would order that Bowling’s execution be stayed until further notice.
. See Woodall v. Commonwealth, 63 S.W.3d 104, 116 (Ky.2002) (upholding trial judge's limitations on voir dire questioning regarding mitigating factors such as low I.Q., noting that defendant's I.Q. scores of 74 and 78 “are 4 to 8 points respectively higher than the definition of a seriously mentally retarded offender as found in KRS 532.130”); Hunter v. Commonwealth, 869 S.W.2d 719, 722 (Ky. 1994) (concluding that the trial court violated due process by failing to grant continuance to permit further testing of defendant, noting that "the doctor's initial judgment that appellant's I.Q. is most likely in the low 70's. The significance of this information, of course, is due to the fact that an I.Q. of seventy is the lower threshold at which a defendant becomes 'death ineligible’ under KRS 532.130(2) and KRS 532.140(1).”) (internal quotation marks omitted); C.I. v. Commonwealth, 2003 WL 22461730, *2 (Ky.Ct.App. Oct.31, 2003) (unpublished) (finding that KBIT test did not qualify as a "full scale” testing measure as required by juvenile-sex-offender statute and could not "satisfy the multifaceted requirements of KRS 532.130(2)”); see also Skaggs v. Parker, 235 F.3d 261, 273 n. 4 (6th Cir.2000) (stating that § 532.140 was not in effect at time of trial but explaining that, under § 532.140, "the court must determine, prior to trial, whether a defendant is mentally retarded. To this end, the court must evaluate a number of factors, including whether the defendant's I.Q. is 70 or below.”).
. Kentucky's mental retardation statute was enacted in 1990 (i.e., prior to Atkins) and appears to have relied on the 1983 version of the AAMR’s mental retardation definition. Bowling v. Commonwealth, 163 S.W.3d 361, 374 (Ky.2005); see Peggy M. Tobolowsky, Atkins Aftermath: Identifying Mentally Retarded Offenders and Excluding Them From Execution, 30 J. Legis. 77, 138 (2003) ("As is abundantly clear, ... Atkins changed the landscape of death penalty jurisprudence. Definitions and procedures that were adequate for a mental retardation determination for purposes of a state execution ban are not necessarily adequate for the enforcement of the Atkins constitutional execution ban.”) (internal quotation and footnotes omitted).
. See Tobolowsky, supra note 2, at 95-96 ("[M]any states have incorporated a specific IQ cutoff score in their definitions of mental retardation, most often using an IQ of seventy as the cutoff for this component of the mental retardation definition. However, most of these definitions do not acknowledge that each assessment instrument has a standard measurement error, usually between three and five points, and that the standard measurement error is not the same for all instruments. Recognizing the impact of the standard measurement error, in the previous AAMR definitions and the current APA definition, the IQ cutoff for mental retardation has been quantified between seventy and seventy-five, as noted by the Court in Atkins. To avoid mistaken reliance on and potential misuse of a particular IQ score, especially if it does not include consideration of standard measurement error, the AAMR stated its current IQ cutoff in terms of being at least two standard deviations below the mean of the specific instruments used, considering their particular standard measurement error, strengths, and limitations. The current APA definitional material also refers to the IQ cutoff as being approximately two standard deviations below the mean, with reference to measurement error of approximately five points. Thus, any state’s use of a fixed IQ cutoff score, without reference to standard measurement error and other factors concerning the specific instrument used, rislcs an inaccurate assessment of the intellectual functioning component of the mental retardation definition.") (emphasis added, footnote omitted); id. at 139 (“[S]tates that use a rigid IQ cutoff score of seventy for the intellectual *444functioning component may be excluding some individuals otherwise falling within the accepted clinical definition.”); Bob Egelko, California Judging If A Killer is Retarded: State’s Justices Set Framework on Executions, S.F. Chron., Feb. 11, 2005, at B1 ("[Mental health] organizations stopped using IQ scores as decisive measures more than a decade ago but consider an IQ of 70 to 75— below all but 1 to 3 percent of the population — to be evidence of retardation.”); James W. Ellis, Mental Retardation and the Death Penalty: A Guide to State Legislative Issues, 7 & nn. 18-19, at http://www.aamr.org/Read-mg_Room/pdf/state_legislatures_guide.pdf (last accessed July 20, 2005) ("IQ scores alone cannot precisely identify the upper boundary of mental retardation. Generally, mental retardation encompasses everyone with a score of 70 or below. Additionally, it includes some individuals with scores in the low 70s (and even mid-70s), depending on the nature of the testing information. As much as the criminal justice system might prefer to have a hard-and-fast limitation measurable by a single IQ score, it is simply impossible to exclude consideration of other factors about the testing performed on the individual, nor is it possible to ignore the need for clinical judgment by experienced diagnosticians.”) (footnotes omitted).