Did Hall and Moore I announce new substantive rules of federal constitutional law that apply retroactively to cases on collateral review?

QUESTION PRESENTED CAPITAL CASE Atkins v. Virginia, 536 U.S. 304 (2002), decided that the Eighth Amendment “places a substantive restriction on the State’s power to take the life” of an individual with an intellectual disability. Jd. at 321 (quoting Ford v. Wainwright, 477 U.S. 399, 405 (1986)). Twice since Atkins, this Court has answered questions regarding “how intellectual disability should be measured and assessed” by States exercising their “discretion to define the full scope of the constitutional protection.” Hall v. Florida, 572 U.S. 701, 719 (2014). The Court first rejected a rule that had treated anyone with a score over 70 on an IQ test as someone who “does not have an intellectual disability” and that had “barred” the person “from presenting other evidence that would show his faculties are limited.” Jd. at 711-12. The Court subsequently decided that “[t]he medical community’s current standards supply one constraint on States’ leeway” to define intellectual disability and, in particular, the “adaptive functioning” criterion for such a disability. Moore v. Texas, 137 8. Ct. 1039, 1050-53 (2017) (Moore J). Lower courts have diverged in three different ways when applying this Court’s federal retroactivity rules to both Hall and Moore I. The decision below joined one group of courts that view both cases as having “adopted new procedures” that do not apply retroactively. App. 28a. That is at odds with a second approach, which applies both Hall and Moore I retroactively after having explained that the former was substantive—not procedural—because it altered how to define a class of people who are subject to a prohibition on capital punishment. And these two approaches are at odds with a third that treats Hall and Moore I as old rules that were dictated by Atkins and, as a result, can apply retroactively. The question presented is: Did Hall and Moore I announce new substantive rules of federal constitutional law that apply retroactively to cases on collateral review? i