Justice Kennedy
delivered the opinion of the Court.
In California, to sentence a defendant to death for first-degree murder the trier of fact must find the defendant guilty , and also find one or more of 19 special circumstances listed in Cal. Penal Code Ann. § 190.2 (West 1988 and Supp. 1994). The case then proceeds to the penalty phase, where the trier of fact must consider a number of specified factors in deciding whether to sentence the defendant to death. §190.3. These two cases present the question whether three of the §190.3 penalty-phase factors are unconstitutionally vague under decisions of this Court construing the Cruel and Unusual Punishments Clause of the Eighth Amendment, made applicable to the States by the Fourteenth Amendment.
I
Petitioner Tuilaepa’s case arises out of a murder he committed in Long Beach, California, in October 1986. Tuilaepa and an accomplice walked into the Wander Inn Bar in Long Beach, where a small crowd had gathered to watch Monday Night Football. Tuilaepa, who was carrying a .22-caliber rifle, approached the bartender, pointed the rifle at him, and demanded money from the cash register. After the bartender turned over the money, Tuilaepa and his accomplice began robbing the bar’s patrons. When the accomplice demanded money from a man named Melvin Whiddon, Whiddon refused and knocked the accomplice to the floor. Tuilaepa shot Whiddon in the neck and next shot Whiddon’s brother, Kelvin, who was standing nearby. Tuilaepa turned to another man, Bruce Monroe, and shot him in the stomach. As Tuilaepa and his accomplice ran toward the back door, they confronted Kenneth Boone. Tuilaepa shot Boone in the neck. Melvin Whiddon died at the scene from the gunshot wounds; the others suffered serious and in some cases permanent injuries.
The State sought the death penalty against Tuilaepa, charging him with the murder of Melvin Whiddon and one special circumstance under § 190.2: murder during the commission of a robbery. The jury found Tuilaepa guilty of first-degree murder and also found the special circumstance true. At the penalty phase, the trial judge instructed the jury to consider the relevant sentencing factors specified in § 190.3. The jury was unanimous in sentencing Tuilaepa to death.
Petitioner Proctor murdered Bonnie Stendal, a 55-year-old schoolteacher who lived in Burney, a small community in Shasta County, California. On a night in April 1982, Proctor entered Mrs. Stendal’s home and beat her, causing numerous cuts and bruises on her face. Proctor stabbed Mrs. Stendal in the neck several times and inflicted seven stab wounds in the area of the right breast. Proctor raped Mrs. Stendal and committed further sexual assaults with a foreign object. After beating, torturing, and raping Mrs. Stendal, Proctor strangled her to death and dumped her body on the side of the road near Lake Britton, 12 miles from Burney. The body was found late the next afternoon, clad in a nightgown with hands tied behind the back.
The State sought the death penalty against Proctor, charging him with murder and a number of special circumstances under § 190.2 including murder during the commission of a rape, murder during the commission of a burglary, and infliction of torture during a murder. The jury found Proctor guilty of murder and found the three special circumstances true. After a mistrial at the penalty phase, Proctor’s motion for change of venue was granted, and a new sentencing jury was empaneled in Sacramento County. The trial judge instructed the jury to consider the sentencing factors specified in § 190.3. The jury was unanimous in sentencing Proctor to death.
Petitioners appealed to the Supreme Court of California, which affirmed their convictions and death sentences. No. 93-5131, 4 Cal. 4th 569, 842 P. 2d 1142 (1992), and No. 93-5161, 4 Cal. 4th 499, 842 P. 2d 1100 (1992). We granted certiorari, 510 U. S. 1010 (1993), and now affirm.
II
A
Our capital punishment cases under the Eighth Amendment address two different aspects of the capital decision-making process: the eligibility decision and the selection decision. To be eligible for the death penalty, the defendant must be convicted of a crime for which the death penalty is a proportionate punishment. Coker v. Georgia, 433 U. S. 584 (1977). To render a defendant eligible for the death penalty in a homicide case, we have indicated that the trier of fact must convict the defendant of murder and find one “aggravating circumstance” (or its equivalent) at either the guilt or penalty phase. See, e. g., Lowenfield v. Phelps, 484 U. S. 231, 244-246 (1988); Zant v. Stephens, 462 U. S. 862, 878 (1983). The aggravating circumstance may be contained in the definition of the crime or in a separate sentencing factor (or in both). Lowenfield, supra, at 244-246. As we have explained, the aggravating circumstance must meet two requirements. First, the circumstance may not apply to every defendant convicted of a murder; it must apply only to a subclass of defendants convicted of murder. See Arave v. Creech, 507 U. S. 463, 474 (1993) (“If the sentencer fairly could conclude that an aggravating circumstance applies to every defendant eligible for the death penalty, the circumstance is constitutionally infirm”). Second, the aggravating circumstance may not be unconstitutionally vague. Godfrey v. Georgia, 446 U. S. 420, 428 (1980); see Arave, supra, at 471 (court “‘must first determine whether the statutory language defining the circumstance is itself too vague to provide any guidance to the sentencer’”) (quoting Walton v. Arizona, 497 U. S. 639, 654 (1990)).
We have imposed a separate requirement for the selection decision, where the sentencer determines whether a defendant eligible for the death penalty should in fact receive that sentence. “What is important at the selection stage is an individualized determination on the basis of the character of the individual and the circumstances of the crime.” Zant, supra, at 879; see also Woodson v. North Carolina, 428 U. S. 280, 303-304 (1976) (plurality opinion). That requirement is met when the jury can consider relevant mitigating evidence of the character and record of the defendant and the circumstances of the crime. Blystone v. Pennsylvania, 494 U. S. 299, 307 (1990) (“requirement of individualized sentencing in capital cases is satisfied by allowing the jury to consider all relevant mitigating evidence”); see Johnson v. Texas, 509 U. S. 350, 361 (1993).
The eligibility decision fits the crime within a defined classification. Eligibility factors almost of necessity require an answer to a question with a factual nexus to the crime or the defendant so as to “make rationally reviewable the process for imposing a sentence of death.” Arave, supra, at 471 (internal quotation marks omitted). The selection decision, on the other hand, requires individualized sentencing and must be expansive enough to accommodate relevant mitigating evidence so as to assure an assessment of the defendant’s culpability. The objectives of these two inquiries can be in some tension, at least when the inquiries occur at the same time. See Romano v. Oklahoma, ante, at 6 (referring to “two somewhat contradictory tasks”). There is one principle common to both decisions, however: The State must ensure that the process is neutral and principled so as to guard against bias or caprice in the sentencing decision. See Gregg v. Georgia, 428 U. S. 153, 189 (1976) (joint opinion of Stewart, Powell, and Stevens, JJ.) (procedures must “minimize the risk of wholly arbitrary and capricious action”). That is the controlling objective when we examine eligibility and selection factors for vagueness. Indeed, it is the reason that eligibility and selection factors (at least in some sentencing schemes) may not be “too vague.” Walton, supra, at 654; see Maynard v. Cartwright, 486 U. S. 356, 361-364 (1988).
Because “the proper degree of definition” of eligibility and selection factors often “is not susceptible of mathematical precision,” our vagueness review is quite deferential. Walton, supra, at 655; see Gregg, supra, at 193-194 (factors “are by necessity somewhat general”). Relying on the basic principle that a factor is not unconstitutional if it has some “common-sense core of meaning . . . that criminal juries should be capable of understanding,” Jurek v. Texas, 428 U. S. 262, 279 (1976) (White, J., concurring in judgment), we have found only a few factors vague, and those in fact are quite similar to one another. See Maynard, supra, at 363-364 (question whether murder was “especially heinous, atrocious, or cruel”); Godfrey, supra, at 427-429 (question whether murder was “outrageously or wantonly vile, horrible and inhuman”); cf. Arave, 507 U. S., at 472 (“We are not faced with pejorative adjectives ... that describe a crime as a whole”). In providing for individualized sentencing, it must be recognized that the States may adopt capital sentencing processes that rely upon the jury, in its sound judgment, to exercise wide discretion. That is evident from the numerous factors we have upheld against vagueness challenges. See, e.g., id., at 472-473 (question whether the defendant was a “cold-blooded, pitiless slayer” is not unconstitutionally vague); Walton, supra, at 654 (question whether “perpetrator inflict[ed] mental anguish or physical abuse before the victim’s death” with “[mjental anguish including] a victim’s uncertainty as to his ultimate fate” is not unconstitutionally vague) (internal quotation marks omitted); Proffitt v. Florida, 428 U. S. 242, 255-258 (1976) (joint opinion of Stewart, Powell, and Stevens, JJ.) (various “mitigating” questions not unconstitutionally vague, nor is the question whether the crime was a “conscienceless or pitiless crime which [wa]s unnecessarily torturous to the victim”) (internal quotation marks omitted); Jurek, supra, at 274-276 (question “whether there is a probability that the defendant would commit criminal acts of violence that would constitute a continuing threat to society” is not unconstitutionally vague).
In our decisions holding a death sentence unconstitutional because of a vague sentencing factor, the State had presented a specific proposition that the sentencer had to find true or false (e.g., whether the crime was especially heinous, atrocious, or cruel). We have held, under certain sentencing schemes, that a vague propositional factor used in the sentencing decision creates an unacceptable risk of randomness, the mark of the arbitrary and capricious sentencing process prohibited by Furman v. Georgia, 408 U. S. 238 (1972). See Stringer v. Black, 503 U. S. 222 (1992). Those concerns are mitigated when a factor does not require a yes or a no answer to a specific question, but instead only points the sentencer to a subject matter. See Cal. Penal Code Ann. §§ 190.3(a), (k) (West 1988). Both types of factors (and the distinction between the two is not always clear) have their utility. For purposes of vagueness analysis, however, in examining the propositional content of a factor, our concern is that the factor have some “common-sense core of meaning ... that criminal juries should be capable of understanding.” Jurek, swpra, at 279 (White, J., concurring in judgment).
B
With those principles in mind, we consider petitioners’ vagueness challenge to the California scheme. A defendant in California is eligible for the death penalty when the jury finds him guilty of first-degree murder and finds one of the §190.2 special circumstances true. See California v. Ramos, 463 U. S. 992, 1008 (1983) (jury found that “the defendant [fell] within the legislatively defined category of persons eligible for the death penalty [by] determining the truth of the alleged special circumstance,” commission of murder during the course of a robbery). (Petitioners do not argue that the special circumstances found in their cases were insufficient, so we do not address that part of California’s scheme save to describe its relation to the selection phase.) At the penalty phase, the jury is instructed to consider numerous other factors listed in § 190.3 in deciding whether to impose the death penalty on a particular defendant. Petitioners contend that three of those § 190.3 sentencing factors are unconstitutional and that, as a consequence, it was error to instruct their juries to consider them. Both Proctor and Tuilaepa challenge factor (a), which requires the sentencer to consider the “circumstances of the crime of which the defendant was convicted in the present proceeding and the existence of any special circumstances found to be true.” Tuilaepa challenges two other factors as well: factor (b), which requires the sentencer to consider “[t]he presence or absence of criminal activity by the defendant which involved the use or attempted use of force or violence or the express or implied threat to use force or violence”; and factor (i), which requires the sentencer to consider “[t]he age of the defendant at the time of the crime.” We conclude that none of the three factors is defined in terms that violate the Constitution.
Petitioners’ challenge to factor (a) is at some odds with settled principles, for our capital jurisprudence has established that the sentencer should consider the circumstances of the crime in deciding whether to impose the death penalty. See, e.g., Woodson, 428 U. S., at 304 (“[Consideration of... the circumstances of the particular offense [is] a constitutionally indispensable part of the process of inflicting the penalty of death”). We would be hard pressed to invalidate a jury instruction that implements what we have said the law requires. In any event, this California factor instructs the jury to consider a relevant subject matter and does so in understandable terms. The circumstances of the crime are a traditional subject for consideration by the sentencer, and an instruction to consider the circumstances is neither vague nor otherwise improper under our Eighth Amendment jurisprudence.
Tuilaepa also challenges factor (b), which requires the sentencer to consider the defendant’s prior criminal activity. The objection fails for many of the same reasons. Factor (b) is phrased in conventional and understandable terms and rests in large part on a determination whether certain events occurred, thus asking the jury to consider matters of historical fact. Under other sentencing schemes, in Texas for example, jurors may be asked to make a predictive judgment, such as “whether there is a probability that the defendant would commit criminal acts of violence that would constitute a continuing threat to society.” See Jurek, 428 U. S., at 269. Both a backward-looking and a forward-looking inquiry are a permissible part of the sentencing process, however, and the States have considerable latitude in determining how to guide the sentencer’s decision in this respect. Here, factor (b) is not vague.
Tuilaepa’s third challenge is to factor (i), which requires the sentencer to consider “[t]he age of the defendant at the time of the crime.” This again is an unusual challenge in light of our precedents. See Eddings v. Oklahoma, 455 U. S. 104, 115-117 (1982) (age may be relevant factor in sentencing decision). The factual inquiry is of the most rudimentary sort, and there is no suggestion that the term “age” is vague. Petitioner contends, however, that the age factor is equivocal and that in the typical case the prosecution argues in favor of the death penalty based on the defendant’s age, no matter how old or young he was at the time of the crime. It is neither surprising nor remarkable that the relevance of the defendant’s age can pose a dilemma for the sentencer. But difficulty in application is not equivalent to vagueness. Both the prosecution and the defense may present valid arguments as to the significance of the defendant’s age in a particular case. Competing arguments by adversary parties bring perspective to a problem, and thus serve to promote a more reasoned decision, providing guidance as to a factor jurors most likely would discuss in any event. We find no constitutional deficiency in factor (i).
C
Petitioners could not and do not take great issue with the conclusion that factors (a), (b), and (i) provide common and understandable terms to the sentencer. Cf. Godfrey, 446 U. S., at 429 (“jury’s interpretation of [outrageously or wantonly vile, horrible and inhuman factor] can only be the subject of sheer speculation”). Petitioners argue, however, that selection factors must meet the requirements for eligibility factors, Brief for Petitioner in No. 93-5161, pp. 10-25, and therefore must require an answer to a factual question, as eligibility factors do. According to petitioners, a capital jury may not be instructed simply to consider an open-ended subject matter, such as “the circumstances of the crime” or “the background of the defendant.” Apart from the fact that petitioners’ argument ignores the obvious utility of these open-ended factors as part of a neutral sentencing process, it contravenes our precedents. Our decisions in Zant and Gregg reveal that, at the selection stage, the States are not confined to submitting to the jury specific propositional questions. In Zant, we found no constitutional difficulty where the jury had been told to consider “‘all facts and circumstances presented in extenuation, mitigation, and aggravation of punishment as well as such arguments as have been presented for the State and for the Defense.’” 462 U. S., at 878-880,889, n. 25. We also stated that “[n]othing in the United States Constitution prohibits a trial judge from instructing a jury that it would be appropriate to take account of a defendant’s prior criminal record in making its sentencing determination.” Id., at 888. And in Gregg, we rejected a vagueness challenge to that same Georgia sentencing scheme in a case in which the “judge ... charged the jury that in determining what sentence was appropriate the jury was free to consider the facts and circumstances, if any, presented by the parties in mitigation or aggravation.” 428 U. S., at 161, 203-204. In both cases, therefore, the Court found no constitutional problem with a death sentence where the jury instructions directed consideration of the “facts and circumstances” of the case. In these cases as well, we must reject petitioners’ suggestion that the Constitution prohibits sentencing instructions that require the trier of fact to consider a relevant subject matter such as the “circumstances of the crime.”
Petitioners also suggest that the § 190.3 sentencing factors are flawed because they do not instruct the sentencer how to weigh any of the facts it finds in deciding upon the ultimate sentence. In this regard, petitioners claim that a single list of factors is unconstitutional because it does not guide the jury in evaluating and weighing the evidence and allows the prosecution (as well as the defense) to make wide-ranging arguments about whether the defendant deserves the death penalty. This argument, too, is foreclosed by our cases. A capital sentencer need not be instructed how to weigh any particular fact in the capital sentencing decision. In California v. Ramos, for example, we upheld an instruction informing the jury that the Governor had the power to commute life sentences and stated that “the fact that the jury is given no specific guidance on how the commutation factor is to figure into its determination presents no constitutional problem.” 463 U. S., at 1008-1009, n. 22. Likewise, in Proffitt v. Florida, we upheld the Florida capital sentencing scheme even though “the various factors to be considered by the sentencing authorities [did] not have numerical weights assigned to them.” 428 U. S., at 258. In Gregg, moreover, we “approved Georgia’s capital sentencing statute even though it clearly did not channel the jury’s discretion by enunciating specific standards to guide the jury’s consideration of aggravating and mitigating circumstances.” Zant, 462 U. S., at 875. We also rejected an objection “to the wide scope of evidence and argument” allowed at sentencing hearings. 428 U. S., at 203-204. In sum, “discretion to evaluate and weigh the circumstances relevant to the particular defendant and the crime he committed” is not impermissible in the capital sentencing process. McCleskey v. Kemp, 481 U. S. 279, 315, n. 37 (1987). “Once the jury finds that the defendant falls within the legislatively defined category of persons eligible for the death penalty, . . . the jury then is free to consider a myriad of factors to determine whether death is the appropriate punishment.” Ramos, supra, at 1008. Indeed, the sentencer may be given “unbridled discretion in determining whether the death penalty should be imposed after it has found that the defendant is a member of the class made eligible for that penalty.” Zant, supra, at 875; see also Barclay v. Florida, 463 U. S. 939, 948-951 (1983) (plurality opinion). In contravention of those cases, petitioners’ argument would force the States to adopt a kind of mandatory sentencing scheme requiring a jury to sentence a defendant to death if it found, for example, a certain kind or number of facts, or found more statutory aggravating factors than statutory mitigating factors. The States are not required to conduct the capital sentencing process in that fashion. See Gregg, supra, at 199-200, n. 50.
The instructions to the juries in petitioners’ cases directing consideration of factor (a), factor (b), and factor (i) did not violate the Constitution. The judgments of the Supreme Court of California are
Affirmed.
Section 190.3 provides in part:
“In determining the penalty, the trier of fact shall take into account any of the following factors if relevant:
“(a) The circumstances of the crime of which the defendant was convicted in the present proceeding and the existence of any special circumstances found to be true pursuant to Section 190.1.
“(b) The presence or absence of criminal activity by the defendant which involved the use or attempted use of force or violence or the express or implied threat to use force or violence.
“(c) The presence or absence of any prior felony conviction.
“(d) Whether or not the offense was committed while the defendant was under the influence of extreme mental or emotional disturbance.
“(e) Whether or not the victim was a participant in the defendant’s homicidal conduct or consented to the homicidal act.
“(f) Whether or not the offense was committed under circumstances which the defendant reasonably believed to be a moral justification or extenuation for his conduct.
“(g) Whether or not defendant acted under extreme duress or under the substantial domination of another person.
“(h) Whether or not at the time of the offense the capacity of the defendant to appreciate the criminality of his conduct or to conform his conduct to the requirements of law was impaired as a result of mental disease or defect, or the [ejffects of intoxication.
“(i) The age of the defendant at the time of the crime.
“(j) Whether or not the defendant was an accomplice to the offense and his participation in the commission of the offense was relatively minor.
“(k) Any other circumstance which extenuates the gravity of the crime even though it is not a legal excuse for the crime.”