opinion: SCHRIRO, DIRECTOR, ARIZONA DEPARTMENT OF CORRECTIONS v. SMITH
  No. 04-1475.
  Decided October 17, 2005
  Per Curiam.
  In 1982, an Arizona jury convicted respondent Robert Douglas Smith of first-degree murder, kidnaping, and sexual assault. He was sentenced to death. The convictions and sentence were affirmed on direct appeal, and Smith’s state petitions for posteonviction relief proved unsuccessful. Smith then filed a petition for a writ of habeas corpus in the United States District Court for the District of Arizona. In none of these proceedings did Smith argue that he was mentally retarded or that his mental retardation made him ineligible for the death penalty. Smith had, however, presented evidence in mitigation during the sentencing phase of his trial showing that he had low intelligence.
  The District Court denied Smith’s petition for habeas corpus in 1996. Following several rounds of appeals, remands, and petitions for certiorari to this Court (including one successful petition by the State, see Stewart v. Smith, 536 U. S. 856 (2002) (per curiam)), and after we had issued our decision in Atkins v. Virginia, 536 U. S. 304 (2002), the case returned to the Ninth Circuit. Shortly thereafter, Smith asserted in briefing that he is mentally retarded and cannot, under Atkins, be executed. The Ninth Circuit ordered suspension of all federal habeas proceedings and directed Smith to “institute proceedings in the proper trial court of Arizona to determine whether the state is prohibited from executing [Smith] in accordance with Atkins.” App. to Pet. for Cert. A-2. The court further ordered that the issue whether Smith is mentally retarded must “be determined ... by a jury trial unless the right to a jury is waived by the parties.” Ibid.
  The State’s petition for certiorari is granted, the judgment of the Court of Appeals is vacated, and the case is remanded. The Ninth Circuit erred in commanding the Arizona courts to conduct a jury trial to resolve Smith’s mental retardation claim. Atkins stated in clear terms that “ ‘we leave to the State[s] the task of developing appropriate ways to enforce the constitutional restriction upon [their] execution of sentences.’ ” 536 U. S., at 317 (quoting Ford v. Wainwright, 477 U. S. 399, 416-417 (1986); modifications in original). States, including Arizona, have responded to that challenge by adopting their own measures for adjudicating claims of mental retardation. While those measures might, in their application, be subject to constitutional challenge, Arizona had not even had a chance to apply its chosen proee-dures when the Ninth Circuit pre-emptively imposed its jury trial condition.
  Because the Court of Appeals exceeded its limited authority on habeas review, the judgment below is vacated, and the case is remanded for further proceedings consistent with this opinion.
  It is so ordered.
  Srmth’s motion to proceed informa pauperis is also granted.
choices: involuntary confession habeas corpus plea bargaining: the constitutionality of and/or the circumstances of its exercise retroactivity (of newly announced or newly enacted constitutional or statutory rights) search and seizure (other than as pertains to vehicles or Crime Control Act) search and seizure, vehicles search and seizure, Crime Control Act contempt of court or congress self-incrimination (other than as pertains to Miranda or immunity from prosecution) Miranda warnings self-incrimination, immunity from prosecution right to counsel (cf. indigents appointment of counsel or inadequate representation) cruel and unusual punishment, death penalty (cf. extra legal jury influence, death penalty) cruel and unusual punishment, non-death penalty (cf. liability, civil rights acts) line-up discovery and inspection (in the context of criminal litigation only, otherwise Freedom of Information Act and related federal or state statutes or regulations) double jeopardy ex post facto (state) extra-legal jury influences: miscellaneous extra-legal jury influences: prejudicial statements or evidence extra-legal jury influences: contact with jurors outside courtroom extra-legal jury influences: jury instructions (not necessarily in criminal cases) extra-legal jury influences: voir dire (not necessarily a criminal case) extra-legal jury influences: prison garb or appearance extra-legal jury influences: jurors and death penalty (cf. cruel and unusual punishment) extra-legal jury influences: pretrial publicity confrontation (right to confront accuser, call and cross-examine witnesses) subconstitutional fair procedure: confession of error subconstitutional fair procedure: conspiracy (cf. Federal Rules of Criminal Procedure: conspiracy) subconstitutional fair procedure: entrapment subconstitutional fair procedure: exhaustion of remedies subconstitutional fair procedure: fugitive from justice subconstitutional fair procedure: presentation, admissibility, or sufficiency of evidence (not necessarily a criminal case) subconstitutional fair procedure: stay of execution subconstitutional fair procedure: timeliness subconstitutional fair procedure: miscellaneous Federal Rules of Criminal Procedure statutory construction of criminal laws: assault statutory construction of criminal laws: bank robbery statutory construction of criminal laws: conspiracy (cf. subconstitutional fair procedure: conspiracy) statutory construction of criminal laws: escape from custody statutory construction of criminal laws: false statements (cf. statutory construction of criminal laws: perjury) statutory construction of criminal laws: financial (other than in fraud or internal revenue) statutory construction of criminal laws: firearms statutory construction of criminal laws: fraud statutory construction of criminal laws: gambling statutory construction of criminal laws: Hobbs Act; i.e., 18 USC 1951 statutory construction of criminal laws: immigration (cf. immigration and naturalization) statutory construction of criminal laws: internal revenue (cf. Federal Taxation) statutory construction of criminal laws: Mann Act and related statutes statutory construction of criminal laws: narcotics includes regulation and prohibition of alcohol statutory construction of criminal laws: obstruction of justice statutory construction of criminal laws: perjury (other than as pertains to statutory construction of criminal laws: false statements) statutory construction of criminal laws: Travel Act, 18 USC 1952 statutory construction of criminal laws: war crimes statutory construction of criminal laws: sentencing guidelines statutory construction of criminal laws: miscellaneous jury trial (right to, as distinct from extra-legal jury influences) speedy trial miscellaneous criminal procedure (cf. due process, prisoners' rights, comity: criminal procedure)