492 U.S. 302 (1989)
On the morning of October 25, 1979, Pamela Carpenter was brutally raped, beaten, and stabbed with a pair of scissors in her home in Livingston, Texas.1 She died a few hours later in the course of emergency treatment. Before she died, she described her assailant. Her description led two local sheriff's deputies to suspect Penry, who had recently been released on parole after conviction on another rape charge. Penry subsequently gave two statements confessing to the crime and was charged with capital murder.2
At a competency hearing held before trial, a clinical psychologist, Dr. Jerome Brown, testified that Penry was mentally retarded. As a child, Penry was diagnosed as having organic brain damage, which was probably caused by trauma to the brain at birth. Penry was tested over the years as having an IQ between 50 and 63, which indicates mild to moderate retardation.3 Dr. Brown's own testing before the trial indicated that Penry had an IQ of 54. Dr. Brown's evaluation also revealed that Penry, who was 22 years old at the time of the crime, had the mental age of a 6 1/2-year-old. Penry's social maturity, or ability to function in the world, was that of a 9- or 10-year-old.4
The guilt-innocence phase of the trial began on March 24, 1980.5 At trial, Penry raised an insanity defense and presented the testimony of a psychiatrist, Dr. Jose Garcia.6 Dr. Garcia testified that Penry suffered from organic brain damage and moderate retardation, which resulted in poor impulse control and an inability to learn from experience.7 Penry's mother testified at trial that Penry was unable to learn in school and never finished the first grade. Penry's sister testified that their mother had frequently beaten him over the head with a belt when he was a child. Penry was also routinely locked in his room without access to a toilet for long periods of time.8 The State introduced the testimony of two psychiatrists to rebut the testimony of Dr. Garcia. Dr. Kenneth Vogtsberger testified that although Penry was a person of limited mental ability, he was not suffering from any mental illness or defect at the time of the crime, and that he knew the difference between right and wrong and had the potential to honor the law.9 Dr. Felix Peebles also testified for the State that Penry was legally sane at the time of the offense and had a full-blown anti-social personality.10
The jury rejected Penry's insanity defense and found him guilty of capital murder. The following day, at the close of the penalty hearing, the jury decided the sentence to be imposed on Penry by answering three special issues.11 Defense counsel raised objections to the proposed charge to the jury, including that the charge failed to define the term "deliberately" and failed to authorize a discretionary grant of mercy based upon the existence of mitigating circumstances and that, in light of Penry's mental retardation, permitting the jury to assess the death penalty in this case amounted to cruel and unusual punishment prohibited by the Eighth Amendment.12 The jury answered yes to all three special issues, and Penry was sentenced to death. The Texas Court of Criminal Appeals affirmed his conviction and sentence on direct appeal. This Court denied certiorari on direct review.13
Penry then filed this federal habeas corpus petition challenging his death sentence. Among other claims, Penry argued that he was sentenced in violation of the Eighth Amendment because the trial court failed to instruct the jury on how to weigh mitigating factors in answering the special issues.14 The District Court denied relief, and Penry appealed to the Court of Appeals for the Fifth Circuit.15 The Court of Appeals affirmed the District Court's judgment.16 The Supreme Court granted certiorari to resolve two questions.17
Whether Penry was sentenced to death in violation of the Eighth Amendment because the jury was not instructed that it could consider and give effect to his mitigating evidence in imposing its sentence?18
Under the Eighth Amendment, as interpreted in Lockett v. Ohio and Eddings v. Oklahoma, the sentencer must be able to consider and give effect to all relevant mitigating evidence offered by the defendant as the basis for a sentence less than death.19 The Texas special issues must allow the jury to fully consider mitigating evidence of mental retardation and abused background in determining whether death is appropriate.20
Yes. Penry presented evidence of his mental retardation with an IQ of 54 and mental age of 6 1/2, organic brain damage, and history of childhood abuse including beatings by his mother.21 The jury was instructed only to answer the three special issues regarding deliberateness, future dangerousness, and response to provocation.22 The evidence of mental retardation was relevant to moral culpability beyond the scope of the special issues, as it could diminish blameworthiness while suggesting future dangerousness.23
Without instructions allowing the jury to give mitigating effect to this evidence, a juror believing Penry did not deserve death could not express that view.24 The prosecutor's argument emphasized following the law and the special issues, leaving no vehicle for mercy based on mitigation.25 The Court of Appeals noted that there was no place for the jury to say 'no' to the death penalty based on the mitigating force of those circumstances.26 Therefore, the jury instructions violated the Eighth Amendment requirement of individualized sentencing.27
Penry's death sentence violated the Eighth Amendment due to inadequate jury instructions on mitigating evidence.28
Related opinions on this issue
Joined by Justice Marshall
Justice Brennan agreed that the jury instructions deprived Penry of his constitutional right to have a jury consider all mitigating evidence before sentencing him to die.29 He joined Parts I, II-B, and III of the opinion.30 Brennan dissented from the extension of Teague to capital cases without briefing but accepted that the mitigating evidence claim did not create a new rule.31
He emphasized that the difference between life and death should not turn on the fortuity of timing in announcing constitutional rules and stressed that full consideration of mitigating evidence is essential to a reasoned moral response.32
Joined by Justice Blackmun
Justice Stevens joined Parts I, II-B, and III of the opinion.33 He agreed that the discussion of the mitigating evidence question does not establish a new rule for retroactivity purposes.34 Stevens assumed arguendo that Teague principles apply to capital cases but noted that the Court's analysis of the instructions compellingly shows the constitutional violation.35
He would have reversed the judgment of the Court of Appeals in its entirety on this ground as well as the mental retardation claim.36
Joined by Chief Justice Rehnquist, Justice White, And Justice Kennedy
Justice Scalia dissented on the mitigating evidence issue.37 He argued that the claim was foreclosed by Jurek v. Texas, which upheld the facial validity of the Texas special issues on the assurance that they permitted consideration of particularized mitigating factors.38 Scalia contended that the Texas scheme channels discretion by focusing the jury on deliberateness, future dangerousness, and provocation, and that requiring additional vehicles for mercy would eliminate the structure needed to avoid arbitrary imposition of the death penalty.39
He viewed the majority's approach as demanding unguided emotional responses rather than reasoned consideration.40
Whether the Eighth Amendment categorically prohibits Penry's execution because he is mentally retarded?41
The Eighth Amendment prohibits cruel and unusual punishments, determined by reference to evolving standards of decency as evidenced by legislation and jury behavior.42 A categorical prohibition on executing mentally retarded persons would require objective evidence of a national consensus against the practice and that it makes no measurable contribution to acceptable goals of punishment or is grossly disproportionate to culpability.43
No. Penry was found competent to stand trial and the jury rejected his insanity defense, reflecting that he knew his conduct was wrong and could conform to the law.44 Only one State currently bans execution of the mentally retarded at the time.45 Public opinion polls indicated opposition, but legislation provides the clearest objective evidence and was insufficient to show a national consensus.46 Mental retardation varies widely in degree and impact; individuals with Penry's mild to moderate level (IQ 54) do not inevitably lack the cognitive and moral capacity to act with the culpability associated with capital punishment.47
The insanity defense and requirements for individualized sentencing already account for reduced culpability through mitigation rather than a categorical exemption.48 Execution of the mentally retarded does not invariably fail retributive or deterrent purposes when sentencers can consider the disability as mitigation.49
The Eighth Amendment does not categorically prohibit the execution of mentally retarded persons like Penry.50
Related opinions on this issue
Joined by Justice Marshall
Justice Brennan would hold that the Eighth Amendment prohibits execution of mentally retarded offenders because they lack the full degree of responsibility that is a predicate for the constitutional imposition of the death penalty.51 He argued that mental retardation, by clinical definition, involves substantial disabilities in cognitive ability and adaptive behavior that limit culpability so that death is always disproportionate.52 Brennan further contended that individualized sentencing fails to isolate lack of culpability as a determinative bar and that execution serves neither retribution nor deterrence given the impairments in reasoning, foresight, and impulse control that define the condition.53
Joined by Justice Blackmun
Justice Stevens concluded that the competing arguments, particularly those advanced by the American Association on Mental Retardation and related amici, compel the conclusion that executions of mentally retarded persons are unconstitutional.54 He joined the retroactivity analysis in Part IV-A but would have reversed the Court of Appeals judgment in full, finding that the evidence of reduced moral capacity and the absence of measurable contribution to penological goals render the punishment cruel and unusual under both proportionality and purposeless-infliction strands of Eighth Amendment doctrine.55
Joined by Chief Justice Rehnquist, Justice White, And Justice Kennedy
Justice Scalia joined the holding rejecting a categorical prohibition. He agreed that execution of mentally retarded offenders contravenes neither those practices condemned at the time the Bill of Rights was adopted nor the evolving standards of decency. Scalia emphasized that the inquiry into whether the punishment makes no measurable contribution to goals of punishment or is disproportionate has no place in Eighth Amendment jurisprudence; the punishment is either cruel and unusual as a matter of societal condemnation or it is not.56