with whom Justice Brennan, Justice Marshall, and Justice Stevens join, dissenting.
In my view, two Arizona statutory provisions, pertinent here, run afoul of the established Eighth Amendment principle that a capital defendant is entitled to an individualized sentencing determination which involves the consideration of all relevant mitigating evidence. The first is the requirement that the sentencer may consider only those mitigating circumstances proved by a preponderance of the evidence. The second is the provision that the defendant bears the burden of establishing mitigating circumstances “sufficiently substantial to call for leniency.” I also conclude that Arizona’s “heinous, cruel or depraved” aggravating circumstance, as construed by the Arizona Supreme Court, provides no meaningful guidance to the sentencing authority and, as a consequence, is unconstitutional.
I therefore dissent from the Court’s affirmance of Jeffrey Alan Walton’s sentence of death.
I
During the past 15 years, this Court’s death penalty jurisprudence consistently has stressed the importance of an individualized-sentencing process, one that permits “the particularized consideration of relevant aspects of the character and record of each convicted defendant before the imposition upon him of a sentence of death.” Woodson v. North Carolina, 428 U. S. 280, 303 (1976) (plurality opinion). Such a procedure is required because “[a] process that accords no significance to relevant facets of the character and record of the individual offender or the circumstances of the particular offense excludes from consideration in fixing the ultimate punishment of death the possibility of compassionate or mitigating factors stemming from the diverse frailties of humankind.” Id., at 304. A plurality of this Court stated in *678Lockett v. Ohio, 438 U. S. 586, 604 (1978), that a capital sentencer may “not be precluded from considering, as a mitigating factor, any aspect of a defendant’s character or record and any of the circumstances of the offense that the defendant proffers as a basis for a sentence less than death.” (Emphasis in original.) In Eddings v. Oklahoma, 455 U. S. 104, 114-115 (1982), a majority held that “[t]he sentencer, and the [state appellate court] on review, may determine the weight to be given relevant mitigating evidence. But they may not give it no weight by excluding such evidence from their consideration.”1 The Court, moreover, has insisted that the substance as well as the form of Lockett must be respected. See Penry v. Lynaugh, 492 U. S. 302, 319 (1989) (“[I]t is not enough simply to allow the defendant to present mitigating evidence to the sentencer. The sentencer must also be able to consider and give effect to that evidence in imposing sentence”).
From those holdings two closely related principles emerge. The first is that the “qualitative difference” between death and all other penalties necessitates a greater degree of “reliability in the determination that death is the appropriate punishment in a specific case.” Woodson v. North Carolina, 428 U. S., at 305 (plurality opinion). The second is that the particularized sentencing procedure mandated by the Eighth Amendment requires that the sentencer be allowed to consider “any aspect of a defendant’s character or record and any of the circumstances of the offense that the defendant proffers as a basis for a sentence less than death.” Lockett v. Ohio, 438 U. S., at 604 (plurality opinion). Only if the defendant is allowed an unrestricted opportunity to present relevant mitigating evidence will a capital sentencing procedure be deemed sufficiently reliable to satisfy constitutional standards. The Court said in Eddings that “the rule in Lockett *679recognizes that a consistency produced by ignoring individual differences is a false consistency.” 455 U. S., at 112.
The Court today upholds an Arizona statute which (a) excludes from the sentencer’s consideration all mitigating circumstances that the defendant has failed to prove by a preponderance of the evidence, and (b) places upon the capital defendant the burden of demonstrating that the mitigating circumstances so proved are “sufficiently substantial to call for leniency.” The plurality makes no effort to explain how these provisions are consistent with the Eighth Amendment principles announced in Woodson, Lockett, and their progeny.2 Indeed, the plurality’s analysis of these issues in-*680eludes virtually no discussion of capital cases, and those that the majority does discuss are demonstrably inapposite. Rather, the plurality relies on “analogous” cases that do not involve the death penalty. Its analysis thereby ignores what I had thought to be settled principles regarding the distinctive nature of capital sentencing.
A
The Arizona capital sentencing statute flatly provides: “[T]he burden of establishing the existence of the [mitigating] circumstances included in subsection G of this section is on the defendant.” Ariz. Rev. Stat. Ann. §13-703(0 (1989). The Arizona Supreme Court has construed the statute to require that any mitigating circumstances must be proved by a preponderance of the evidence. See, e. g., State v. McMurtrey, 143 Ariz. 71, 73, 691 P. 2d 1099, 1101 (1984). There can be no doubt that this provision of Arizona law excludes from the sentencer’s consideration relevant mitigating evidence that might affect the determination whether the death penalty is appropriate. Exclusion of that evidence is unsupported by this Court’s decisions and serves no legitimate state interest.
The plurality does not analyze this case within the framework established by our Eighth Amendment decisions. Rather, the plurality relies almost exclusively on noncapital cases upholding the State’s right to place upon the defendant the burden of proving an affirmative defense. See ante, at 650. Reliance on these cases is misplaced, however, since those decisions rest upon a premise that is wholly inapplicable in the capital sentencing context. In Patterson v. New York, 432 U. S. 197 (1977), the Court explained the justification in a noncapital case for allowing the burden of persuasion as to affirmative defenses to be placed upon the defendant rather than the State:
“The Due Process Clause, as we see it, does not put New York to the choice of abandoning those defenses or un*681dertaking to disprove their existence in order to convict of a crime which otherwise is within its constitutional powers to sanction by substantial punishment.
. . [I]n each instance of a murder conviction under the present law, New York will have proved beyond a reasonable doubt that the defendant has intentionally killed another person, an act which it is not disputed the State may constitutionally criminalize and punish. If the State nevertheless chooses to recognize a factor that mitigates the degree of criminality or punishment, we think the State may assure itself that the fact has been established with reasonable certainty. To recognize at all a mitigating circumstance does not require the State to prove its nonexistence in each case in which the fact is put in issue, if in its judgment this would be too cumbersome, too expensive, and too inaccurate.” Id., at 207-209 (emphasis added).
The Court’s decision thus rested upon an argument that “the greater power includes the lesser”: since the State constitutionally could decline to recognize the defense at all, it could take the lesser step of placing the burden of proof upon the defendant. That reasoning is simply inapposite when a capital defendant introduces mitigating evidence, since the State lacks the greater power to exclude the evidence entirely.3
But it makes no sense to analyze petitioner’s claim of Lockett error by drawing on “analogous” cases outside the sphere of capital sentencing. In developing the requirement *682of individualized capital sentencing (with unlimited presentation of relevant mitigating evidence), this Court has not purported to rely on principles applicable to criminal prosecutions generally. Instead, the Court’s Eighth Amendment jurisprudence explicitly has proceeded from the premise “that death is a punishment different from all other sanctions in kind rather than degree.” Woodson v. North Carolina, 428 U. S., at 303-304 (plurality opinion).4 To suggest that the principles announced in Lockett and Eddings are applicable only insofar as they are consistent with the constitutional rules governing noncapital cases is to deprive those decisions of all significance.
Application of the preponderance standard in this context is especially problematic in light of the fact that the “existence” of a mitigating factor frequently is not a factual issue to which a “yes” or “no” answer can be given. See Stebbing v. Maryland, 469 U. S. 900, 902-904 (1984) (Marshall, J., dissenting from denial of certiorari). The statute, for example, lists as a first mitigating circumstance the fact that “[t]he defendant’s capacity to appreciate the wrongfulness of his conduct or to conform his conduct to the requirements of law was significantly impaired . . . .” Ariz. Rev. Stat. Ann. § 13— 703(G)(1) (1989). Petitioner offered evidence of childhood sexual abuse. Presumably, no individual who suffers such treatment is wholly unaffected; at the same time, it is rare that such an individual is so deeply traumatized that his impairment furnishes a complete defense for his actions. The question whether an individual’s capacity to behave lawfully is “impaired” is one of degree, not an either/or propo*683sition. The preponderance standard, however, encourages the sentencer to conclude that unless some vaguely defined threshold of “significance” has been reached, the evidence of abuse and consequent impairment cannot be considered at all.
Indeed, it appears that the Arizona Supreme Court has applied the statute in just this fashion. See, e. g., State v. Wallace, 151 Ariz. 362, 369, 728 P. 2d 232, 239 (1986) (“[W]e find that neither defendant’s ‘difficult earlier years’ nor his use of ‘various drugs’ so affected his capacity to conform to the requirements of law that they constitute mitigating factors under § 13 — 703(G)(1)”), cert. denied, 483 U. S. 1011 (1987); State v. Rossi, 146 Ariz. 359, 367, 706 P. 2d 371, 379 (1985) (intoxication or duress is not a mitigating circumstance unless it is substantial); State v. Woratzeck, 134 Ariz. 452, 458, 657 P. 2d 865, 871 (1982) (same); State v. Nash, 143 Ariz. 392, 406, 694 P. 2d 222, 236 (State acknowledged some degree of mental impairment but argued that “it was not significant enough to be a mitigating circumstance”), cert. denied, 471 U. S. 1143 (1985). The Arizona Supreme Court has not simply held that duress or impairment which falls below the threshold should be given reduced weight at the final stage of the sentencing process, when aggravating and mitigating circumstances are balanced. Rather, it has held that duress or impairment which falls below the threshold is not a mitigating factor. It is therefore misleading, in many instances, to characterize an Arizona court’s rejection of proffered mitigating evidence as a determination that the evidence should not be credited. The trial judge instead may be acting upon the belief that a defendant’s impairment, though proved, is not “significant” within the meaning of the statute. Thus, under Arizona law, a sentencing judge is entitled to give no weight to mitigating evidence on the ground that the evidence is not mitigating enough. Under the guise of a burden of proof, *684the statute provides that some mitigating evidence is not to be considered at all. 3
Even when the trial judge’s rejection of a particular mitigating circumstance is based on credibility determinations, application of the preponderance standard is unwarranted. Mitigating evidence that fails to meet this standard is not so unreliable that it has no proper place in the sentencing decision: Decisions as to punishment, like decisions as to guilt or innocence, will often be based on the cumulative effect of several pieces of evidence, no one of which by itself is fully persuasive. The problems with the preponderance standard are compounded when the defendant presents several possible mitigating factors. A trial judge might be 49% convinced as to each of 10 mitigating circumstances; yet he would be forced to conclude, as a matter of law, that there was no mitigation to weigh against the aggravating factors.
The Arizona Supreme Court has articulated two closely related justifications for placing upon the capital defendant the burden of proving that a mitigating circumstance exists. The court has asserted that “[f ]acts which would tend to show mitigation are peculiarly within the knowledge of a defendant,” State v. Smith, 125 Ariz. 412, 416, 610 P. 2d 46, 50 (1980), and that “[t]o require the State to negate every mitigating circumstance would place an impermissible burden on the State,” State v. Watson, 120 Ariz. 441, 447, 586 P. 2d *6851253, 1259 (1978), cert. denied, 440 U. S. 924 (1979). Until today, this Court has never identified a state interest which outweighs the capital defendant’s right to unrestricted presentation of mitigating evidence. Even if such an interest could exist, however, the interests advanced by the State in support of the preponderance standard do not withstand scrutiny.
The State’s justifications are not without force when a criminal defendant offers an affirmative defense in a trial to determine guilt or innocence. A jury’s decision as to an affirmative defense is a binary choice: either the defense is accepted or it is not. Since the jury’s acceptance of the defense automatically results in an acquittal (or in conviction on a lesser charge), the State may suffer real prejudice if the defense is established on the basis of minimally persuasive evidence which the State has no practical opportunity to rebut — especially if it is difficult to anticipate the defenses that a particular individual may offer. In contrast, if a capital sentencer believes that certain mitigating evidence has some persuasive value, but does not meet the preponderance standard, the sentencer simply may give that evidence reduced weight — weight proportional to its persuasiveness — at the final balancing stage.6 No legitimate interest is served *686by forbidding the sentencer to give such evidence any effect at all.
The Arizona rule at issue here falls well within the prohibition announced in Lockett and its progeny. The statute defines a wide range of relevant mitigating evidence — evidence with some degree of persuasiveness which has not been proved by a preponderance — that cannot be given effect by the capital sentencer. That rule finds no support in this Court’s precedents, and it serves no legitimate governmental interest. I therefore conclude that the Arizona death penalty statute, as construed by the Supreme Court of Arizona, impermissibly limits the sentencer’s consideration of relevant mitigating evidence, and thereby violates the Eighth Amendment.7
B
I also believe that the Constitution forbids the State of Arizona to place upon the capital defendant the burden of proving mitigating circumstances that are “sufficiently substantial to call for leniency.” Ariz. Rev. Stat. Ann. § 13-703(E) (1989). Once an aggravating circumstance has been established, the Arizona statute mandates that death is to be deemed the appropriate penalty unless the defendant proves otherwise. That statutory provision, in my view, establishes a “presumption of death” 8 in violation of the Eighth Amendment.
*687The Arizona Supreme Court repeatedly has indicated that a defendant’s mitigating evidence will be deemed “sufficiently substantial to call for leniency” only if the mitigating factors “outweigh” those in aggravation.9 That court has sustained the requirement on the ground that “[w]hen the issue of guilt is settled and only the question of punishment remains, due process is not offended by requiring the already guilty defendant to carry the burden of showing why he should receive leniency.” State v. Watson, 120 Ariz., at 447, 586 P. 2d, at 1259. If the mitigating and aggravating circumstances are in equipoise, the statute requires that the trial judge impose capital punishment. The assertion that a sentence of death may be imposed in such a case runs directly counter to the Eighth Amendment requirement that a capital sentence must rest upon a “determination that death is the appropriate punishment in a specific case.” Woodson v. North Carolina, 428 U. S., at 305 (plurality opinion).
The plurality takes a hard-line approach and makes little effort to ground its holding on our Eighth Amendment jurisprudence. In support of its position, the plurality cites only two very recent capital cases, Blystone v. Pennsylvania, 494 U. S. 299 (1990), and Boyde v. California, 494 U. S. 370 (1990). Reliance even on these precedents is misplaced. The statutes upheld in those cases provided that the death penalty would be imposed “only after a determination that the aggravating circumstances outweigh the mitigating circumstances present in the particular crime committed by the particular defendant, or that there are no such mitigating circumstances.” Blystone, 494 U. S., at 305. In neither Boyde nor Blystone did the challenged statute require a capi*688tal sentence when aggravating and mitigating factors are evenly balanced. Those decisions simply do not speak to the issue posed by the Arizona statute: whether the State permissibly may place upon the capital defendant the burden of demonstrating that a sentence of death is not appropriate.
The plurality does not attempt to explain why Arizona may require a capital sentence in a case where aggravating and mitigating circumstances are evenly balanced.10" Indeed, the plurality does not even acknowledge that this is the dispositive question. Instead, it offers only a conclusory assertion: “So long as a State’s method of allocating the burdens of proof does not lessen the State’s burden to prove every element of the offense charged, or in this case to prove the existence of aggravating circumstances, a defendant’s constitutional rights are not violated by placing on him the burden of proving mitigating circumstances sufficiently substantial to call for leniency.” Ante, at 650. One searches in vain for any hint of a limiting principle. May a State require that the death penalty be imposed whenever an aggravating factor is established and mitigating circumstances do not “substantially outweigh” those in aggravation? May a state statute provide that a death sentence is presumptively appropriate whenever an aggravating circumstance is proved, and that the presumption can be rebutted only by a showing that mitigating circumstances are “extraordinarily great”? These formulations would appear to satisfy the plurality’s test: viz., that the State is required to establish an aggravating circumstance, and no mitigating evidence is excluded from the sen-tencer’s consideration.11 But the right to present mitigating *689evidence is rendered all but meaningless if the rules that guide the sentencer’s deliberations virtually ensure that the mitigating evidence will not change the outcome.12
Like the plurality’s analysis of the requirement that mitigating circumstances be proved by a preponderance of the evidence, its approval of this provision appears to rest upon an analogy between mitigating evidence in capital sentencing and affirmative defenses in noncapital cases. In noncapital cases, of course, the States are given broad latitude to sacrifice precision for predictability by imposing determinate sentences and restricting the defendant’s ability to present evidence in mitigation or excuse. If the States were similarly free to make capital punishment mandatory for specified crimes, and to prohibit the introduction of mitigating evidence or declare such evidence to be irrelevant, the plurality’s reasoning today would be unassailable. There then could be no objection to a sentencing scheme which permitted a defendant to argue that the death penalty was inappropriate in his case, but placed upon his shoulders the burden of persuading the sentencer. This Court, however, repeatedly has recognized that the “qualitative difference between death and other penalties calls for a greater degree of reliability when the death sentence is imposed,” Lockett v. Ohio, 438 U. S., at 604 (plurality opinion), and that in capital cases “the punishment should be directly related to the personal culpability of the defendant,” Penry v. Lynaugh, 492 U. S., at 327. I see no way that these principles can be squared with *690a capital sentencing scheme which provides that doubtful cases should be resolved in favor of a sentence of death. I therefore conclude that the Constitution bars Arizona from placing upon a capital defendant the burden of proving that mitigating circumstances are “sufficiently substantial to call for leniency.”
II
In Godfrey v. Georgia, 446 U. S. 420 (1980), we considered Georgia’s “outrageously or wantonly vile, horrible or inhuman” aggravating circumstance. The plurality concluded: “There is nothing in these few words, standing alone, that implies any inherent restraint on the arbitrary and capricious infliction of the death sentence. A person of ordinary sensibility could fairly characterize almost every murder as ‘outrageously or wantonly vile, horrible and inhuman.’” Id., at 428-429. Two Terms ago, in Maynard v. Cartwright, 486 U. S. 356 (1988), the Court unanimously struck down an Oklahoma death sentence based in part upon that State’s “especially heinous, atrocious, or cruel” aggravating circumstance. The Court noted that “the language of the Oklahoma aggravating circumstance at issue . . . gave no more guidance than the ‘outrageously or wantonly vile, horrible or inhuman’ language that the jury returned in its verdict in Godfrey.” Id., at 363-364.
The Arizona statute at issue today lists as an aggravating circumstance the conclusion that “[t]he defendant committed the offense in an especially heinous, cruel or depraved manner.” Ariz. Rev. Stat. Ann. § 13-703(F)(6) (1989) (the (F)(6) circumstance). The Arizona Supreme Court consistently has held that “[t]hese terms are considered disjunctive; the presence of any one of three factors is an aggravating circumstance.” State v. Beaty, 158 Ariz. 232, 242, 762 P. 2d 519, 529 (1988), cert. denied, 491 U. S. 910 (1989). At the sentencing phase in the present case, the State relied primarily on medical evidence detailing the injuries that the victim Powell suffered when he regained consciousness after the *691shooting.13 The trial judge’s sentencing order stated that he found that Walton had “committed the offense in an extremely heinous, cruel or depraved manner,” App. 56, but did not specify the basis for that finding. In its “independent review” of the capital sentence, the Arizona Supreme Court held that the (F)(6) circumstance was not supported by evidence of Powell’s suffering after the shooting, since Walton could not have foreseen that Powell would survive his wound. The court found, however, that the murder was especially cruel since “Powell suffered great mental anguish both during the car ride when his fate was uncertain and in his final march into the desert when his fate had become certain.” 159 Ariz. 571, 587, 769 P. 2d 1017, 1033 (1989). The court also indicated that a finding of depravity would be supported by Walton’s comment some hours after the shooting that he had “never seen a man pee in his pants before.” Ibid.
In sustaining Walton’s sentence of death, the majority offers two principal grounds upon which, it says, Godfrey and Maynard may be distinguished. First, the majority points out that capital sentencing in Arizona is conducted by a trial judge who is presumed to be aware of any limiting construction announced by the State Supreme Court. Ante, at 653. Second, the majority notes that the Arizona Supreme Court itself “purport[ed] to affirm the death sentence by applying a limiting definition of the aggravating circumstance to the facts presented.” Ibid. In my view, neither of these factors supports the Court’s decision to affirm petitioner’s death sentence.
*692A
Unlike a jury, a sentencing judge is presumed to know the law as stated in the controlling opinions of the State Supreme Court. Even if the aggravating circumstance is vague on its face, the sentence will be valid if the judge’s discretion has been suitably channeled by the “instructions” provided by the appellate court’s construction of the statute. The trial judge’s familiarity with the State Supreme Court’s opinions, however, will serve to narrow his discretion only if that body of case law articulates a construction of the aggravating circumstance that is coherent and consistent, and that meaningfully limits the range of homicides to which the aggravating factor will apply.14 One therefore would expect the majority to analyze Arizona Supreme Court decisions issued prior to the imposition of petitioner’s sentence (Jan. 27, 1987), in order to determine whether the judge who sentenced Walton to death can be presumed to have acted on the basis of a constitutionally sufficient limiting construction of the aggravating factor. The Court, however, cites no Arizona cases at all, justifying the omission as a refusal to second-guess the State Supreme Court’s proportionality review. Ante, at 655-656. The Court thus distinguishes Godfrey and Maynard on the ground that Arizona sentencing judges are presumed to read and be guided by the opinions of the Arizona Supreme Court, yet insists, as a matter of principle, that it is barred from determining whether those opinions furnish con*693stitutionally adequate guidance. This, it seems to me, is strange and unusual reasoning indeed.15
Had the majority examined the Arizona Supreme Court’s application of the “especially heinous, cruel or depraved” aggravating circumstance, it would have been hard pressed to conclude that the state court has placed meaningful limitations on the scope of the (F)(6) factor. The Arizona Supreme Court attempted to define the statutory terms in State v. Knapp, 114 Ariz. 531, 562 P. 2d 704 (1977), cert. denied, 435 U. S. 908 (1978). The court there stated: “The words ‘heinous, cruel or depraved’ have meanings that are clear to a person of average intelligence and understanding.” 114 Ariz., at 543, 562 P. 2d, at 716. The court then offered definitions culled from Webster’s Third New International Dictionary: “heinous” was defined as “hatefully or shockingly evil: grossly bad”; “cruel” as “disposed to inflict pain esp. in a wanton, insensate or vindictive manner: sadistic”; and “depraved” as “marked by debasement, corruption, perversion or deterioration.” Ibid.16’ The court explained: “What our *694legislature intended to include as an aggravating circumstance was a killing wherein additional circumstances of the nature enumerated above set the crime apart from the usual or the norm.” Ibid.
In State v. Gretzler, 135 Ariz. 42, 659 P. 2d 1, cert. denied, 461 U. S. 971 (1983), the Arizona Supreme Court reviewed its prior decisions construing the (F)(6) factor. The court explained that “cruelty involves the pain and distress visited upon the victims, and that heinous and depraved go to the mental state and attitude of the perpetrator as reflected in his words and actions.” 135 Ariz., at 51, 659 P. 2d, at 10.17 The court also listed five factors that, in prior cases, had supported a finding that a particular killing was especially heinous or depraved. These factors were (1) “the apparent relishing of the murder by the killer,” (2) “the infliction of gratuitous violence on the victim,” (3) “the needless mutilation of the victim,” (4) “the senselessness of the crime,” and (5) “the helplessness of the victim.” Id., at 52, 659 P. 2d, at 11. The court did not disavow the Knapp definitions; to the contrary, it cited those definitions with approval. 135 Ariz., at 51, 659 P. 2d, at 10. Nor did the court hold that a murder could be deemed especially heinous or depraved only when one of these five factors was present. Rather, the court stated: “Where no circumstances, such as the specific factors discussed above, separate the crime from the ‘norm’ of first degree murders, we will reverse a finding that the crime was committed in an ‘especially heinous, cruel, or depraved manner.’” Id., at 53, 659 P. 2d, at 12 (emphasis added).
The principles announced in Gretzler have failed to place meaningful limitations on the application of the (F)(6) ag*695gravating circumstance. Since its decision in Gretzler, the Arizona Supreme Court has continued to identify new factors which support a finding that a particular murder was heinous or depraved. The court, for example, has held that heinousness or depravity was shown in part by the age of the victim, see State v. Wallace, 151 Ariz., at 368, 728 P. 2d, at 238 (“[T]he fact that defendant killed two children, with whom he admittedly had no dispute and who posed no danger to him, is additional evidence of his ‘shockingly evil state of mind’”); State v. Zaragoza, 135 Ariz. 63, 69, 659 P. 2d 22, 28 (“The victim in this case was 78 years old”), cert. denied, 462 U. S. 1124 (1983); by the fact the murder was committed to eliminate a witness, see State v. Correll, 148 Ariz. 468, 481, 715 P. 2d 721, 734 (1986); State v. Gillies, 142 Ariz. 564, 570, 691 P. 2d 655, 661 (1984), cert. denied, 470 U. S. 1059 (1985); State v. Smith, 141 Ariz. 510, 511-512, 687 P. 2d 1265, 1266-1267 (1984); by the fact the victim had been kind to the killer, State v. Fisher, 141 Ariz. 227, 252, 686 P. 2d 750, 775, cert. denied, 469 U. S. 1066 (1984); by the fact the killer used “special bullets . . . designed to inflict greater tissue damage,” State v. Rossi, 146 Ariz., at 365, 706 P. 2d, at 377, or “intentionally and repeatedly fir[ed] a high-powered, destructive weapon at the victim,” State v. Chaney, 141 Ariz. 295, 313, 686 P. 2d 1265, 1283 (1984); by the fact “the victim was bound to an extent far greater than was necessary to achieve” the purpose of preventing her escape, State v. Villafuerte, 142 Ariz. 323, 331, 690 P. 2d 42, 50 (1984), cert. denied, 469 U. S. 1230 (1985); or by the killer’s “total disregard for human life,” State v. Correll, 148 Ariz., at 481, 715 P. 2d, at 734. The Arizona Supreme Court has not purported to announce necessary conditions for a finding of heinousness or depravity. Instead, the court has observed: “Our previous cases have approved findings of heinous or depraved conduct where the perpetrator acted with gratuitous violence, relished the killing or in some other way acted in such a fashion that his acts set him apart from the ‘norm’ of first degree murderers.” *696State v. Johnson, 147 Ariz. 395, 401, 710 P. 2d 1050, 1056 (1985) (emphasis added).
Indeed, there would appear to be few first-degree murders which the Arizona Supreme Court would not define as especially heinous or depraved — and those murders which do fall outside this aggravating circumstance are likely to be covered by some other aggravating factor. Thus, the court will find heinousness and depravity on the basis of “gratuitous violence” if the murderer uses more force than necessary to kill the victim, see State v. Summerlin, 138 Ariz. 426, 436, 675 P. 2d 686, 696 (1983); State v. Ceja, 126 Ariz. 35, 40, 612 P. 2d 491, 496 (1980), but the murder will be deemed cruel if the killer uses insufficient force and the victim consequently dies a lingering death, see State v. Chaney, 141 Ariz., at 312, 686 P. 2d, at 1282. A determination that a particular murder is “senseless” will support a finding of depravity; but a murder to eliminate a witness is also depraved, a murder for pecuniary gain is covered by a separate aggravating circumstance,18 and evidence showing that the defendant killed out of hatred for the victim or a desire for revenge may be used to buttress the court’s conclusion that the killer “relished” the crime. *697See State v. Jeffers, 135 Ariz. 404, 430, 661 P. 2d 1105, 1131, cert. denied, 464 U. S. 865 (1983).19 In State v. Wallace, 151 Ariz., at 368, 728 P. 2d, at 238, the court’s determination that the crime was “senseless” (and therefore heinous and depraved) was based in part on the fact that the defendant “steadfastly maintains there was no reason or justification for what he did” — this in a case where the defendant argued that his remorse for the crime constituted a mitigating factor.
I must also conclude that the Arizona Supreme Court’s construction of “cruelty” has become so broad that it imposes no meaningful limits on the sentencer’s discretion. The court in State v. Knapp, 114 Ariz., at 543, 562 P. 2d, at 716, used a dictionary definition to regard “ ‘cruel’ ” as “ ‘disposed to inflict pain esp. in a wanton, insensate or vindictive manner: sadistic.’” This might have provided the starting point for a limiting construction that would have meaningfully distinguished the most egregious murders. This Court in Maynard expressed apparent approval of a construction that would limit the aggravating circumstance to murders involving “torture or serious physical abuse.” 486 U. S., at 364; accord, Godfrey v. Georgia, 446 U. S., at 431 (plurality opinion). And I have no quarrel with the proposition that a murder which is preceded by the deliberate infliction of gratuitous suffering is more blameworthy than one which is not.
*698The Arizona Supreme Court’s later decisions, however, made it clear that the murder which is “especially cruel” is the norm rather than the exception. The application of this circumstance has been expanded to cover any murder in which the victim is shown to have experienced fear or uncertainty as to his ultimate fate.20" The Arizona Supreme Court has not required that the defendant must have deliberately delayed or protracted the killing for the purpose of causing the victim mental anguish. Nor has the court required that the period of fear or uncertainty be of extended duration: The court has made findings of cruelty in cases where that period was brief.21 Indeed, in explaining the sorts of murder that would not be especially cruel, the Arizona Supreme Court has repeatedly referred to killings in which the victim was not conscious, see, e. g., State v. Beaty, 158 Ariz., at 242, 762 P. 2d, at 529 (“[T]o suffer pain or distress, the victim must be conscious at the time the offense is committed. If the evidence is inconclusive on consciousness, the factor of cruelty cannot exist”), cert. denied, 491 U. S. 910 (1989),22 and has explained that the victim of an “especially cruel” killing is “to be contrasted with the individual who is killed instantly without knowing what happened.” State v. Gillies, 142 Ariz. 564, 570, 691 P. 2d 655, 661 (1984), cert. denied, 470 U. S. 1059 (1985). I do not believe that an aggravating factor *699which requires only that the victim be conscious and aware of his danger for some measurable period before the killing occurs can be said to provide a “principled way to distinguish this case, in which the death penalty was imposed, from the many cases in which it was not.” Godfrey v. Georgia, 446 U. S., at 433 (plurality opinion). And I am entirely baffled by the majority’s assertion that this construction of the aggravating circumstance is “virtually identical,” ante, at 655, to a requirement of torture or serious physical abuse.23
The majority is correct in asserting that, in the absence of evidence to the contrary, the trial judge who sentenced petitioner to death must be presumed to have been aware of the manner in which these statutory terms had been construed by the Arizona Supreme Court. That judge’s familiarity with the applicable precedents, however, could not possibly have served to guide or channel his sentencing discretion. The entire body of Arizona case law, like the bare words of the statute, provided “no principled way to distinguish this case” from other homicides where capital sentences were not imposed. Under this Court’s decisions in Godfrey and Maynard, the standards by which the trial court sentenced Walton to death were constitutionally deficient.
B
Relying on Clemons v. Mississippi, 494 U. S. 738 (1990), the majority also contends that “a state appellate court may itself determine whether the evidence supports the existence of the aggravating circumstance as properly defined .... *700[T]he Arizona Supreme Court has sought to give substance to the operative terms, and we find that its construction meets constitutional requirements.” Ante, at 654. The Court thus holds that, even if the trial-level sentencing procedure failed to satisfy the Eighth Amendment, Walton’s sentence nevertheless may stand because the appellate court, applying a satisfactory limiting construction, independently determined that the murder was especially cruel. For three independent reasons, I cannot accept that conclusion.
(1) If the (F)(6) factor and the prior decisions of the Arizona Supreme Court failed to provide sufficient guidance to the trial judge, the appellate court’s conclusion that this murder fell within some narrow definition of “cruel” could not eliminate the possibility that the trial court, in balancing aggravating and mitigating circumstances, had relied on factors lying outside this narrow definition. Affirmance of Walton’s death sentence depends not only on the Arizona Supreme Court’s determination that this murder was especially cruel, but also upon its conclusion that the mitigating factors did not outweigh those in aggravation. I adhere to the view, expressed in the separate opinion in Clemons, 494 U. S., at 756, which three other Justices joined, that an appellate court is incapable of finding and balancing aggravating and mitigating factors in a manner that is sufficiently reliable to satisfy the Eighth Amendment.-'24 Indeed, the Arizona Supreme Court’s treatment of the record in this case hardly provides support for those Members of this Court — a bare majority — who now would entrust the task of capital sentencing to an appellate tribunal. The state court’s conclusion that the murder was especially cruel was based in large part *701on its assertions that Powell “was so clearly terrified by the time they stopped that [one of the assailants] tried to reassure him that they would not hurt him” and that during the final march into the desert the victim “begged the defendant not to kill him.” 159 Ariz., at 587, 769 P. 2d, at 1033. The court’s discussion includes no citations to the record (which furnishes frail support for the court’s characterization of the events), and appears to be based primarily on a misreading of the State’s appellate brief.25 Given the institutional limitations of appellate courts generally, and the questionable treatment of the facts by the Arizona Supreme Court in this case, I cannot agree that the appellate sentencing here was sufficiently reliable to meet the standards of the Eighth Amendment.26
*702(2) In Clemons, this Court stated that, insofar as the Federal Constitution is concerned, a state appellate court may determine for itself whether a capital sentence is warranted when the trial-level sentencing proceeding has been tainted by constitutional error. Whether the supreme court of a particular State possesses that power, however, is a matter of state law.27 The Arizona Supreme Court has taken obviously inconsistent positions on the question whether trial-level error in capital sentencing necessitates a remand, or whether the error may be cured by the appellate court’s independent review. Compare State v. Wallace, 151 Ariz., at 369, 728 P. 2d, at 239 (“As we have set aside the finding of pecuniary gain, we must now allow the trial court another opportunity to exercise its sentencing discretion and reweigh the remaining aggravating and mitigating factors”); State v. Rossi, 146 Ariz., at 368, 706 P. 2d, at 380 (“Because we believe the trial judge used the wrong standard for determining and applying mitigating factors, we must vacate defendant’s death sentence and remand for resentencing”); State v. McMurtrey, 143 Ariz. 71, 73, 691 P. 2d 1099, 1101 (1984) (“Because the trial judge imposed upon the defendant a more onerous burden of proof in determining the existence of mitigating circumstances, the matter will have to be remanded for resentencing”); State v. Gillies, 135 Ariz. 500, 516, 662 P. *7032d 1007, 1023 (1983) (court remanded for resentencing after three of four aggravating circumstances found by the trial judge were invalidated on appeal), with State v. Rockwell, 161 Ariz. 5, 15-16, 775 P. 2d 1069, 1079-1080 (1989) (court invalidated two of three aggravating circumstances and concluded that the mitigating evidence outweighed the remaining aggravating factor); State v. Poland, 144 Ariz. 388, 407, 698 P. 2d 183, 202 (1985) (“The finding that the murders were committed in an ‘especially heinous, cruel or depraved manner’ is set aside, but the findings as to the other aggravating circumstances are affirmed. No mitigating circumstances sufficiently substantial to call for leniency have been shown”); State v. James, 141 Ariz. 141, 148, 685 P. 2d 1293, 1300 (court struck down one aggravating factor but upheld the death sentence on the ground that “[tjhere is [another] aggravating circumstance and no mitigating circumstances sufficiently substantial to call for leniency”), cert, denied, 469 U. S. 990 (1984); State v. Blazak, 131 Ariz. 598, 604, 643 P. 2d 694, 700 (one aggravating factor invalidated, but death sentence upheld because “[e]ven in the absence of this aggravating circumstance, there are still enough aggravating circumstances that cannot be overcome by the mitigating circumstances”), cert. denied, 459 U. S. 882 (1982).28 It simply is not clear whether the Arizona Supreme Court regards itself as having the power to uphold a capital sentence on the basis of its own comparison of aggravating and mitigating circumstances when the sentencing judge has relied in part upon an invalid aggravating factor.
In this case, as in all capital cases, the Arizona Supreme Court performed an “independent review” of the trial-level *704sentencing process. The Arizona Supreme Court consistently has maintained: “Unlike appellate review of non-capital crimes, our duty on review of the death penalty is to conduct an independent examination of the record to determine whether the death penalty was properly imposed.” State v. Schad, 129 Ariz. 557, 573, 633 P. 2d 366, 382 (1981), cert. denied, 455 U. S. 983 (1982). The independent review performed by the Arizona Supreme Court in capital cases, however, is quite different from appellate “reweighing” as that term is used in Clemons. The Arizona court’s review does not proceed from the premise that errors in the trial-level sentencing process can be cured by the State Supreme Court’s determination that death is the appropriate penalty. Rather, that review historically has been explained as an additional level of protection for the defendant, a means of ensuring that a trial judge’s sentence of death is subjected to rigorous scrutiny. See State v. Richmond, 114 Ariz. 186, 196, 560 P. 2d 41, 51 (1976) (“The gravity of the death penalty requires that we painstakingly examine the record to determine whether it has been erroneously imposed”), cert. denied, 433 U. S. 915 (1977). Under Arizona law, the trial court is the sentencer, and the appellate court’s review is intended to ensure that trial-level functions were properly carried out. Indeed, the Arizona Supreme Court has resisted analogies between its own independent review and the initial trial-level sentencing process: “While we have an independent duty of review, we perform it as an appellate court, not as a trial court. . . . We hold, therefore, that the Arizona procedure is not a single indivisible hearing, but instead resembles a trial on the issue of life or death followed by the utilization of this court’s appellate process . . . .” State v. Rumsey, 136 Ariz. 166, 173, 665 P. 2d 48, 55 (1983).29 To*705day’s majority indicates, however, that the Arizona Supreme Court’s independent review may serve as a substitute for a constitutionally adequate trial-level sentencing proceeding, despite the fact that the State Supreme Court did not believe that any trial-level error had occurred and regarded itself as affirming the sentencing decision of the lower court.
Whether or not the Arizona Supreme Court possesses the power to “reweigh” evidence in order to cure trial-level error, it is clear that the court did not purport to exercise that power in this case. The court did not suggest that the trial judge’s finding of the (F)(6) circumstance was constitutionally suspect. The Arizona Supreme Court made independent determinations as to aggravating and mitigating circumstances, but these findings were plainly intended to supplement rather than to replace the findings of the trial court. That this is a distinction with a difference should be clear to the present majority from this Court’s opinion in Caldwell v. Mississippi, 472 U. S. 320 (1985). In Caldwell we invalidated a capital sentence imposed by a jury which had been incorrectly informed that its verdict was only a “recommendation. ” We stated that “it is constitutionally impermissible to rest a death sentence on a determination made by a sentencer who has been led to believe that the responsibility for determining the appropriateness of the defendant’s death rests elsewhere.” Id., at 328-329. The same reasoning should apply here. Just as a jury’s sentence of death may not stand if the jury believed that it was merely recommending capital punishment, the Arizona Supreme Court’s independent determination that death is appropriate cannot cure trial-level error if the appellate court believed in*706correctly that it was simply affirming a constitutionally valid sentence imposed by the trial judge.
Thus, even if I could accept the majority’s conclusion that appellate resentencing can cure constitutional defects in the trial-level procedure, I could not agree that the Arizona Supreme Court has purported to exercise that power here. To conclude that Walton’s death sentence may stand, despite constitutional defects in the trial-level sentencing process, it is not enough for the majority to say that the Constitution permits a state appellate court to reweigh valid aggravating and mitigating factors. The majority must also be prepared to assert with reasonable assurance that the Arizona Supreme Court would have chosen to affirm the death sentence on the basis of its own reweighing if it had recognized that the trial-level procedure was defective. Given the Arizona court’s inconsistent treatment of the reweighing issue, no such assertion is possible. In holding that the appellate court’s independent review can save the sentence even if the trial judge received insufficient guidance, the majority affirms a decision that the Arizona Supreme Court never made.
(3) Even if I believed that appellate resentencing could cure trial-level error, and that the Arizona Supreme Court can properly be regarded as the sentencer in this case, I would still conclude that petitioner’s sentence must be vacated. The (F)(6) aggravating factor, as construed by the State Supreme Court, sweeps so broadly that it includes within its reach virtually every homicide. The appellate court’s application of the statutory language simply provides no meaningful basis on which a defendant such as Walton can be singled out for death.
Indeed, my conclusion that the sentence imposed by the appellate court is invalid follows almost necessarily from my belief that the trial-level sentencing was constitutionally flawed.30 The defective nature of the trial court’s sentence *707did not stem from the judge’s failure to abide by limitations announced by the Arizona Supreme Court. Rather, the trial-level sentencing procedure was defective because, even assuming that the trial judge correctly applied the relevant precedents, those decisions had failed to articulate a constitutionally sufficient narrowing construction of the statutory language. In the two years between the trial court’s imposition of sentence and its own affirmance, the Arizona Supreme Court did not purport to narrow the scope of the (F)(6) aggravating factor. It therefore is difficult to see how any trial-level error could have been cured by the appellate court’s application of the same legal rules that the trial judge is presumed to have followed.
The majority concedes, as it must, that the statutory language is unconstitutionally vague under Godfrey and Maynard. The majority therefore recognizes that the validity of the (F)(6) factor depends upon the construction given it by the Arizona Supreme Court. I do not see how the adequacy of that construction can be determined other than through examination of the body of state-court precedents — an examination that the majority conspicuously declines to undertake. Because the Arizona Supreme Court has utterly failed to place meaningful limits on the application of this aggravating factor, a sentence based in part upon the (F)(6) circumstance should not stand.31
*708HH t — I I — I
Earlier this Term the very same majority of this Court severely restricted the regime of federal habeas corpus that had previously helped to safeguard the constitutional rights of criminal defendants, including those accused of capital crimes. See Butler v. McKellar, 494 U. S. 407 (1990); Saffle v. Parks, 494 U. S. 484 (1990). Today this majority serves notice that capital defendants no longer should expect from this Court on direct review a considered examination of their constitutional claims. In adjudicating claims that will mean life or death for convicted inmates in Arizona and elsewhere, the majority makes only the most perfunctory effort to reconcile its holding with this Court’s prior Eighth Amendment jurisprudence. Nor does the majority display any recognition that a decision concerning the constitutionality of a State’s capital punishment scheme may require an understanding of the manner in which that scheme actually operates.
Perhaps the current majority has grown weary of explicating what some Members no doubt choose to regard as hyper-technical rules that currently govern the administration of the death penalty. Certainly it is to be hoped that States will scrupulously protect the constitutional rights of capital defendants even without the prospect of meaningful federal oversight. Good wishes, however, are no substitute for this Court’s careful review. Today’s decision is either an abdication of the Court’s constitutional role, or it is a silent repudiation of previously settled legal principles.
I dissent.
The Court in Eddings further instructed that on remand “the state courts must consider all relevant mitigating evidence and weigh it against the evidence of the aggravating circumstances.” 456 U. S., at 117.
The plurality does assert, however, that its analysis is consistent with Lockett and its progeny. See ante, at 649-650. In contrast, Justice Scalia, who provides the fifth vote for affirmance, expresses no view on the question whether the Arizona statute comports with the standards announced in the Court’s prior decisions. He argues, instead, that any violation of Lockett is immaterial because Lockett should be overruled. Eight Members of the Court agree that Lockett remains good law, and I shall not attempt today a detailed exposition of this Court’s Eighth Amendment jurisprudence. I do wish, however, to make two brief observations:
First, Justice Scalia’s argument is not new — as his citation to then-Justice Rehnquist’s dissent in Lockett demonstrates. See ante, at 667. The rule that a capital sentencer must be allowed to consider all relevant mitigating evidence has been vigorously opposed, intensely debated, and eventually accepted by all Members of this Court as a common starting point for analysis in individual cases. See, e. g., Hitchcock v. Dugger, 481 U. S. 393 (1987) (Scalia, J., writing for a unanimous Court). This history suggests not only that considerations of stare decisis support continued application of the Lockett rule. It indicates as well that this Court’s Eighth Amendment jurisprudence is not so patently irrational that it should be abruptly discarded.
My second observation relates to the integrity of this Court's adjudicative process. The validity of Lockett has been presumed throughout this case, and the arguments raised by Justice Scalia have not been addressed in petitioner's brief or argument. It is disturbing that the decisive vote in a capital case should turn on a single Justice's rejection of a line of authority that both parties to this controversy, and eight Members of this Court, have accepted.
This is not the first time a Member of this Court has recognized the connection between the State's greater power to eliminate all consideration of mitigating evidence and its lesser power to place the burden of proof on the defendant. See Lockett v. Ohio, 438 U. S. 586, 633 (1978) (Rehn-Ql’iST, J., concurring in part and dissenting in part) (“Because I continue to believe that the Constitution is not offended by the State's refusal to consider mitigating factors at all, there can be no infirmity in shifting the burden of persuasion to the defendant when it chooses to consider them").
The plurality in Lockett stated: “We recognize that, in noncapital cases, the established practice of individualized sentences rests not on constitutional commands, but on public policy enacted into statutes. . . . Given that the imposition of death by public authority is so profoundly different from all other penalties, we cannot avoid the conclusion that an individualized decision is essential in capital cases.” Id., at 604-605.
One might ask what would happen if the defendant argued that he had proved the mitigating circumstance of “moderate impairment.” Presumably the Arizona Supreme Court would respond that no such mitigating factor is recognized under Arizona law. In prior decisions indicating that certain proffered evidence of impairment or duress would not constitute a mitigating factor, that court has relied on the language of the Arizona statute, which requires that impairment be “significant” and duress “substantial.” See, e. g., State v. Rossi, 146 Ariz. 359, 366-367, 706 P. 2d 371, 378-379 (1985). Rejection of mitigating evidence on the ground that it does not support a mitigating circumstance an defined in the statute, however, cannot be reconciled with Hitchcock v. Dugger, 481 U. S. 393 (1987), in which this Court held that a capital defendant cannot be restricted to proof of statutory mitigating factors.
See Eddings v. Oklahoma, 455 U. S. 104, 114-115 (1982) ("The sen-tencer, and the [state appellate court] on review, may determine the weight to be given relevant mitigating evidence. But they may not give it no weight by excluding such evidence from their consideration”).
As the Arizona Supreme Court has recognized, the determination that an aggravating or mitigating factor exists does not require that the factor be given any particular weight. “The statute does not require that the number of aggravating circumstances be weighed against the number of mitigating circumstances. One mitigating circumstance, for example, may be ‘sufficiently substantial’ to outweigh two aggravating circumstances. The converse is also true — one aggravating circumstance could be so substantial that two or more mitigating circumstances would not be ‘sufficiently substantial to call for leniency. A. R. S. § 13-454(D).”' State v. Brookover, 124 Ariz. 38, 42, 601 P. 2d 1322, 1326 (1979).
Nor is Arizona’s decision to place the burden of proving mitigation on the defendant saved by the fact that the State is required to prove aggravating circumstances beyond a reasonable doubt. See McCleskeg v. Kemp, 481 U. S. 279, 304 (1987) (“In contrast to the carefully defined standards that must narrow a sentencer’s discretion to impone the death sentence, the Constitution limits a State’s ability to narrow a sentencer’s discretion to consider relevant evidence that might cause it to decline to impose the death sentence”) (emphasis in original).
See Adamson v. Ricketts, 865 F. 2d 1011, 1041 (CA9 1988) (en banc), cert, pending, No. 88-1553. See also Jackson v. Dugger, 837 F. 2d 1469, 1474 (CA11), cert. denied, 486 U. S. 1026 (1988).
See, e. g., State v. McCall, 160 Ariz. 119, 125, 770 P. 2d 1165, 1171 (1989); State v. Mauro, 159 Ariz. 186, 208, 766 P. 2d 59, 81 (1988); State v. Moorman, 154 Ariz. 578, 587, 744 P. 2d 679, 688 (1987); State v. LaGrand, 153 Ariz. 21, 37, 734 P. 2d 563, 579, cert. denied, 484 U. S. 872 (1987); State v. McMurtrey, 151 Ariz. 105, 110, 726 P. 2d 202, 207 (1986), cert. denied, 480 U. S. 911 (1987).
The State’s asserted interest in ensuring that only “reliable" evidence is considered at the final balancing stage of course provides no basis for a requirement that death be imposed whenever the mitigating evidence found to be reliable evenly balances the aggravating circumstances.
The fact that the presumption of death is triggered only by the finding of an aggravating circumstance does not save the statute. See Sumner v. Shuman, 483 U. S. 66, 78 (1987) (proof of an aggravating factor “doles] not provide an adequate basis on which to determine whether the death sen*689tence is the appropriate sanction in any particular case"; capital defendant is still entitled to individualized consideration of mitigating evidence).
See Penry v. Lynaugh, 492 U. S. 302, 319 (1989) C‘[I]t is not enough simply to allow the defendant to present mitigating evidence to the sentencer. The sentencer must also be able to consider and give effect to that evidence in imposing sentence"); Franklin v. Lynaugh, 487 U. S. 164, 185 (1988) (O’Connor, J., concurring in judgment) ("Indeed, the right to have the sentencer consider and weigh relevant mitigating evidence would be meaningless unless the sentencer was also permitted to give effect to its consideration").
Defense counsel objected to the introduction of this testimony on the ground that Walton could not have foreseen Powell’s suffering after the shooting, since Walton reasonably believed that Powell was dead. The trial judge overruled the objection on the ground that “the testimony that I understand he's going to testify to certainly goes to cruelty. ..." Tr. 233 (Jan. 26, 1987).
The Arizona Supreme Court stated: “[T]he trial court’s finding of cruelty is supported by the mental torment of the victim prior to the shooting rather than the events which took place afterwards.” 159 Ariz. 571, 587, 769 P. 2d 1017, 1033 (1989). The trial judge, however, made no ‘‘finding of cruelty”: he found more generally that Walton “committed the offense in an extremely heinous, cruel or depraved manner. ” The trial judge's sentence therefore can stand only if all three of the statutory terms have been given constitutionally sufficient limiting constructions.
The majority relies on our holding in Pulley v. Harris, 465 U. S. 37, 43 (1984), in arguing that proportionality review is not constitutionally required. Ante, at 655-656. That reliance is misplaced. In Pulley the Court held that, so long as other safeguards at the initial sentencing proceeding adequately limit the sentencer’s discretion, the Constitution does not require the additional protection of proportionality review by an appellate court. See 465 U. S., at 44-54. Pulley is simply irrelevant when the adequacy of the initial sentencing is itself the point at issue.
These definitions are strikingly similar to the jury instructions given in Maynard, in which the Oklahoma jury was told that “the term ‘heinous’ means extremely wicked or shockingly evil; ‘atrocious’ means outrageously wicked and vile; ‘cruel’ means pitiless, or designed to inflict a high degree of pain, utter indifference to, or enjoyment of, the sufferings of others.” Cartwright v. Maynard, 822 F. 2d 1477, 1488 (CA10 1987). The majority acknowledges, albeit obliquely, that those instructions were unconstitutionally vague. See ante, at 652-653. The Tenth Circuit’s assessment of the Oklahoma jury instructions is equally applicable to the definitions used in Knapp: “Vague terms do not suddenly become clear when they are de*694fined by reference to other vague terms.” Cartwright v. Maynard, 822 F. 2d, at 1489.
The court also noted that “our concept of cruelty involves not only physical pain, but also ‘mental. . . distress visited upon the victims.'" 135 Ariz., at 51, 659 P. 2d, at 10, quoting State v. Clark, 126 Ariz. 428, 436, 616 P. 2d 888, 896, cert. denied, 449 U. S. 1067 (1980).
See Ariz. Rev. Stat. Ann. § 13-703(F)(5) (1989). Indeed, the Arizona Supreme Court has been willing to find that a particular murder was committed both for an unworthy purpose and for no purpose at all. In State v. Tison, 129 Ariz. 526, 633 P. 2d 335 (1981), cert. denied, 459 U. S. 882 (1982), the Arizona Supreme Court found two aggravating circumstances: (1) the murders were committed for pecuniary gain, since the object of the killings was to obtain an automobile, id., at 542, 633 P. 2d, at 351, and (2) the murders were senseless, and therefore especially heinous and depraved, in part because the victims could not have impeded the theft of the car and the killings therefore did not further the defendants’ plan, id., at 543, 633 P. 2d, at 352. See also State v. Correll, 148 Ariz. 468, 479, 715 P. 2d 721, 732 (1986) (pecuniary gain circumstance was established by the fact that the defendant and an accomplice “very carefully executed the armed robbery, and the murders were part of the scheme of robbery”); id., at 481, 715 P. 2d, at 734 ((F)(6) factor was proved because “depravity is indicated by the senselessness of the murders in that the murders were unnecessary to accomplish the robbery”).
The Arizona Supreme Court has identified other particularly reprehensible motives which, in its view, will support a finding of heinousness or depravity. See State v. Martinez-Vlllaveal, 145 Ariz. 441, 451. 702 P. 2d 670, 680 (murder to demonstrate "manliness” reflects "a manifest disregard for the fundamental principles upon which our society is based"), cert. denied, 474 U. S. 975 (1985): State v. McCall. 139 Ariz. 147, 162, 677 P. 2d 920, 935 (1983) (finding supported in part by the fact that the mutilation of the victims' bodies “was designed to be a 'message' to warn other people"), cert. denied. 467 U. S. 1220 (1984). Taken together, the state court's decisions reflect the indisputable fact that there is no legitimate reason to commit murder, but they provide no principled basis for identifying the most blameworthy killings.
See, e. g., State v. Bracy, 145 Ariz. 520, 537, 703 P. 2d 464, 481 (1985), cert. denied, 474 U. S. 1110 (1986); State v. Carriger, 143 Ariz. 142, 160, 692 P. 2d 991, 1009 (1984), cert. denied, 471 U. S. 1111 (1985); State v. Correll, 148 Ariz., at 480, 715 P. 2d, at 733.
See State v. Rossi, 146 Ariz., at 365, 706 P. 2d, at 377 (“Before defendant fired the fatal shot, the victim leaned against his bedroom wall and pleaded with defendant, stating ‘You have my money, you shot me, what more do you want?’ This evinces the victim’s mental anguish”).
See also State v. Villafuerte, 142 Ariz. 323, 331, 690 P. 2d 42, 50 (1984), cert. denied, 469 U. S. 1230 (1985); State v. Harding, 137 Ariz. 278, 294, 670 P. 2d 383, 399 (1983), cert. denied, 465 U. S. 1013 (1984); State v. Zaragoza, 135 Ariz. 63, 69, 659 P. 2d 22, 28, cert. denied, 462 U. S. 1124 (1983).
The State, focusing on the fear and uncertainty experienced by Powell prior to the shooting, asserts: “It is without question that the victim suffered an excruciatingly ‘cruel’ death,” and suggests that Powell's mental anguish was equivalent to “torture." Brief for Respondent 48-49. I do not minimize Thomas Powell’s suffering, but it bears noting that the State of Arizona seeks to confine Jeffrey Walton in its penitentiary, set a date for his execution, and put him to death. It seems strange for the State to suggest that an individual has been “tortured" when he is made to contemplate the prospect of his own demise.
The discussion of appellate reweighing in Clemons technically is dictum: The Court vacated Clemons’ death sentence but stated that on remand the Mississippi Supreme Court might reweigh the valid aggravating and mitigating circumstances or apply a limiting construction of the challenged aggravating factor if it concluded that under state law it had the power to do so. 494 U. S., at 750-752.
The Arizona Supreme Court’s first assertion is supported only by the following passage from the testimony of Sharold Ramsey:
“Q. How was [Powell] acting after you pulled up at the pullout and they got out of the car?
“A. He was scared.
“Q. How do you know?
“A. I don’t remember. I just told him not to be scared because he wouldn’t be hurt. . . .” App. 24.
The statement that Powell “begged the defendant not to kill him” appears to be based entirely on Walton’s statement during his taped interrogation that “the guy told Rob [one of Walton’s accomplices], he goes, don’t hurt me, I don’t tell anybody, ((inaudible)).” Tr. 82 (Dec. 15, 1986, p.m.).
In its brief to the Arizona Supreme Court, the State asserted, without record citation: “During the ride, Powell begged his abductors to spare him and they could keep his money and car.” Appellee’s Answering Brief in No. CR 87-0022-AP, p. 50. That assertion was made more or less in passing: the State’s argument on cruelty focused on Powell’s mental and physical suffering after the shooting. The Arizona Supreme Court’s opinion asserts that Powell begged for his life when he and Walton were alone in the desert (rather than during the car ride beforehand). There is not one line of testimony that supports the court’s statement.
The trial judge in this case found that Walton rather than Hoover had fired the fatal shot — an issue on which the evidence was conflicting and on which the jury was apparently unable to agree. See 159 Ariz., at 592-593, 769 P. 2d, at 1038-1039 (concurring opinion). In its brief to the Arizona *702Supreme Court, the State argued that this finding should be reviewed deferentially on the ground that “[a]s the trial court is better situated to assess the impact of the evidence, its decision should not be overturned absent abuse of that discretion.” Appellee’s Answering Brief in No. 87-0022-AP, p. 48. The Arizona Supreme Court did not purport to make an independent determination on this point: It stated only that “we find substantial evidence to support the trial judge’s finding that the defendant killed the victim.” 159 Ariz., at 586, 769 P. 2d, at 1032.
See Clemons, 494 U. S., at 754 (“Nothing in this opinion is intended to convey the impression that state appellate courts are required to or necessarily should engage in reweighing or harmless error analysis when errors have occurred in a capital sentencing proceeding. Our holding is only that such procedures are constitutionally permissible”).
See also State v. Smith, 146 Ariz. 491, 504, 707 P. 2d 289, 302 (1985) (“Our elimination of some aggravating factors in the absence of mitigating circumstances does not mandate a remand to the trial court for resentenc-ing”) (emphasis added) (citing cases). Where mitigating factors are absent, affirmance of the death sentence does not require reweighing and is more properly characterized as harmless-error analysis.
In affirming the judgment of the Arizona Supreme Court in that ease, this Court stated that “the availability of appellate review, including reweighing of aggravating and mitigating circumstances, [does not] make the appellate process part of a single continuing sentencing proceeding. The *705Supreme Court of Arizona noted that its role is strictly that of an appellate court, not a trial court. Indeed, no appeal need be taken if life imprisonment is imposed, and the appellate reweighing can work only to the defendant’s advantage." Arizona v. Rumsey, 467 U. S. 203, 210 (1984) (emphasis added). We also referred to the trial judge as “the sole decisionmaker in the proceeding.” Id., at 211.
The one difference is that the trial judge found only that the murder was committed “in an extremely heinous, cruel or depraved manner,” *707while the appellate court specified that the murder was “cruel. ” If the Arizona Supreme Court’s prior decisions had placed meaningful limits on the concept of “cruelty,” that difference might be significant. In fact, however, the state court’s construction of “cruelty” has placed no significant constraints on the sentencer’s discretion — whether the sentencer is the trial judge or the Arizona Supreme Court itself.
The breadth of the (F)(6) circumstance is particularly unfortunate in light of the statutory requirement that the defendant, in order to avoid the death penalty, must demonstrate mitigating factors “sufficiently substantial to call for leniency.” The presumption of death is triggered whenever an aggravating circumstance is found; the Arizona Supreme Court's expan*708sive construction of the (F)(6) factor ensures that an aggravating circumstance plausibly can be discovered in virtually any murder.