Opinion of the Court
B
In 2005, Cruz was convicted and sentenced to death for the murder of a Tucson police officer. Cruz’s conviction occurred over a decade after the decision in Simmons, but became final before the decision in Lynch.
At trial, Cruz repeatedly sought to inform the jury of his parole ineligibility. Citing Simmons, Cruz expressed concern that unless he had “the opportunity to present the mitigating factor that he will not be released from prison,” jurors would be left to “speculate” about Arizona’s capital sentencing scheme and whether it allows for parole. App. 28–29. The trial court “conclude[d] that Simmons is distinguishable” and did not act on Cruz’s concern. Id., at 41.
Cruz also informed the trial court of his intent to call as a witness the chairman of the Arizona Board of Executive Clemency to testify that the board no longer had authority to parole any capital defendants. In response, the State sought to prevent Cruz from offering evidence as to “the prospects of parole for an inmate sentenced to life imprisonment.” Id., at 45. The trial court precluded the testimony.
During the aggravation/mitigation phase of an Arizona capital trial, the jury must first determine whether an aggravating circumstance exists. The jury here found a single aggravating factor that Cruz knowingly killed a police officer. See Ariz. Rev. Stat. Ann. §13–703(F)(10) (2003) (renumbered as §13–751(F)(8)). The jury then heard from 16 defense witnesses who testified to Cruz’s good behavior in prison, his abuse and neglect as a child, his posttraumatic stress disorder, and his history of drug use, including around the time of the offense.
After counsel made closing arguments, the judge instructed the jury that Cruz was eligible for three penalties: (1) “Death by lethal injection”; (2) “Life imprisonment with no possibility of parole or release from imprisonment on any
