Before KING, DENNIS, and OWEN, Circuit Judges.
The petitioner–appellee, Anthony L. Pierce, was sentenced to death in 1986 in Texas state court for a murder committed during the course of a robbery in 1977. After exhausting his state-court avenues for postconviction relief in 2007, he sought habeas relief under 28 U.S.C. § 2254 in federal district court. The district court vacated Pierce’s death sentence and ordered resentencing, finding that the statutory special issues presented to the jury at Pierce’s sentencing did not permit the jury to give meaningful consideration and effect to all of Pierce’s mitigating evidence, as Penry v. Lynaugh, 492 U.S. 302 (1989), requires. The district court denied Pierce’s other asserted bases for habeas relief and denied a certificate of appealability (COA). The State appealed the resentencing. Pierce, in turn, sought a COA from this court on six of the issues raised before the district court. We granted a COA as to two of those issues: Whether Pierce received ineffective assistance of counsel at sentencing, and whether Pierce was mentally retarded and therefore ineligible for the death penalty under Atkins v. Virginia, 536 U.S. 304 (2002).
We now affirm the district court’s grant of resentencing under Penry. Because we affirm resentencing on that basis, we do not address whether Pierce’s ineffective assistance of counsel claim provides an alternate basis for resentencing. We affirm the district court’s denial of habeas relief and an evidentiary hearing on Pierce’s Atkins claim. The reasons for these rulings are explained below.