I concur in the majority’s affirmance of guilt and of the felony-murder special-circumstance finding. I also concur in the setting aside of the special circumstance findings: murder for financial gain, witness-murder and heinous, atrocious or cruel murder. I dissent from the affirmance of the death penalty.
I cannot agree that the jury’s consideration of the three invalid special circumstance findings in this case “was harmless error and could not have affected its penalty verdict.” (Maj. opn., ante, at p. 633.) Rather, this error taken singly was very probably prejudicial, and was certainly so when viewed in combination with the erroneous admission of defendant’s threat to kill a police officer in prison.
We begin by addressing the majority’s assertion that the setting aside of three special circumstance findings in this case does not compel reversal of defendant’s death sentence, for which they cite as authority the decision of the United States Supreme Court in Zant v. Stephens (1983) 462 U.S. 862 [77 L.Ed.2d 235, 103 S.Ct. 2733] and our own opinion in People v. Allen (1986) 42 Cal.3d 1222 [232 Cal.Rptr. 849, 729 P.2d 115]. As will be seen, neither of these decisions is applicable to the present case. The majority also err in their assessment of the prejudicial impact of the excessive special circumstance findings in this particular case.
In Zant, supra, 462 U.S. 862, the United States Supreme Court upheld a death sentence under the Georgia death penalty statute despite the fact that, of the three statutory aggravating circumstances on which the jury had rested its sentencing decision,1 one (that the offense was committed by a *644person having a substantial history of serious assaultive criminal convictions) was later held to be unconstitutionally vague. (462 U.S. at p. 867 [77 L.Ed.2d at pp. 243-244].) Relevant to the court’s holding, however, was the fact that under the Georgia law the statutory aggravating circumstances played no express part in the jury’s consideration of whether a death-eligible defendant should receive the ultimate penalty.2 Of course, the same cannot be said of the California statute, which directs that any special circumstance found true shall also be considered in aggravation at the penalty phase of the capital trial (Pen. Code, § 190.3, factor (a))3 and specifies that the jury shall weigh the aggravating and mitigating factors presented to determine whether death is the appropriate penalty. (§ 190.3, last par.; People v. Brown (1985) 40 Cal.3d 512, 538-541 [220 Cal.Rptr. 637, 709 P.2d 440], revd. on other grounds sub nom. California v. Brown (1987) 479 U.S. 538 [93 L.Ed.2d 934; 107 S.Ct. 837].)
That Zant has no application to the present situation is made clear by the court’s observation there that in upholding the defendant’s conviction under the Georgia statute “we do not express any opinion concerning the possible significance of a holding that a particular aggravating circumstance is ‘invalid’ under a statutory scheme in which the judge or jury is specifically instructed to weigh statutory aggravating and mitigating circumstances in exercising its discretion whether to impose the death penalty.” (462 U.S. at p. 890 [77 L.Ed.2d at p. 258].) In the present case the jury’s death verdict rested in part upon the weight, if any, which it assigned to its earlier finding that defendant’s offense was “heinous, atrocious or cruel” (§ 190.2, subd. (a)(14)), a special circumstance which this court has found must be set aside as unconstitutionally vague. (Maj. opn., ante, at p. 631); People v. Superior Court (Engert) (1982) 31 Cal.3d 797, 806 [183 Cal.Rptr. 800, 647 P.2d 76].) Thus this case presents precisely the situation on which the United States Supreme Court declined to rule in Zant, and on which it has yet to express an opinion.4
*645This case is also readily distinguishable from Allen, supra, 42 Cal.3d 1222. The defendant in Allen was found guilty of three first degree murders, one of them a witness-murder within the meaning of section 190.2, subdivision (a)(10).5 He also had a prior murder conviction. Based on these facts, the prosecutor alleged, and the jury found, eleven special circumstances: three for the prior murder conviction (§ 190.2, subd. (a)(2)), six for multiple murder (§ 190.2, subd. (a)(3)) and two for the witness-murder, based on the two alternative grounds set forth in the statute. (See ante, fn. 5.) This court set aside eight of these eleven findings as improperly duplicative: two of the three arising from the prior murder conviction (42 Cal.3d at p. 1274, citing People v. Harris (1984) 36 Cal.3d 36 [201 Cal.Rptr. 782, 679 P.2d 433]), five of the six multiple-murder special circumstances (42 Cal.3d at p. 1273, also citing Harris, supra) and, despite the presence of both alternative grounds, one of the two witness-murder special circumstances as well. (42 Cal.3d at pp. 1273-1274.)
We found the excessive special-circumstance findings in Allen, supra, 42 Cal.3d 1222, not prejudicial to the penalty decision in that case, since they did not entail the consideration of any evidence not otherwise admissible and relevant to the jury’s decision. We noted that the jury was fully aware of the defendant’s three present murder convictions, including one witness murder, and of his prior murder conviction. The jury was therefore aware— indeed the prosecutor explained to them in precise terms—that the multiple-murder special circumstances involved only three murders and that the witness-murder and prior-murder-conviction special circumstances, despite their numbers, involved only one witness murder and one prior conviction. (Id., at pp. 1281-1282.)
Unlike those at issue in Allen (supra, 42 Cal.3d 1222), two of the excessive special circumstances here—witness-murder and heinous, atrocious or cruel murder—were not merely duplicative of others properly found, they *646were invalid in and of themselves.6 Each involved an improper characterization of the evidence which, but for the finding of a special circumstance, might not have been considered in aggravation at the penalty phase. The jury in Allen did not improperly consider in aggravation the fact that the defendant was before them for three murders, that one of his present victims was killed to prevent testimony and/or in retaliation for prior testimony, and that he had a prior murder conviction. By contrast the jury here was erroneously allowed to consider certain aspects of defendant’s crime— specifically, its findings that the victim was killed to prevent future testimony and that defendant’s offense was “heinous, atrocious or cruel”—not only in aggravation but as circumstances sufficient, each alone, to render defendant eligible for the death penalty.
If, as this court has repeatedly recognized, the consideration of duplicative special circumstances “improperly inflates the risk that the jury will arbitrarily impose the death penalty” (Harris, supra, 36 Cal.3d at p. 67; Allen, supra, 42 Cal.3d at pp. 1273, 1274; People v. Anderson (1987) 43 Cal.3d 1104, 1150 [240 Cal.Rptr. 585, 742 P.2d 1306]), then the possibility of prejudice is only greater where special circumstances have been alleged and found which are invalid even on their own. This possibility of prejudice would have been present even if, as the majority conclude (maj. opn., ante, at pp. 634-635), the prosecutor had not exploited the invalid findings in his closing argument. Contrary to the majority’s view, however, the prosecutor’s references to the invalid special circumstances were repeated ones, and while the thrust of the argument may have been to dwell on the circumstances of the crime in general and the lack of circumstances in mitigation, the effect of those references was to keep alive in the jurors’ minds the improper characterization of certain of the circumstances in aggravation of defendant’s crime.7
*647Where there has been error, the absence of its exploitation by the prosecutor is not in any case dispositive of the issue of prejudice. The jury’s findings here also deprived defendant of any argument he might otherwise have made that, horrible as his offense was, there was no particular aspect in which it was “more horrible” than any other murder committed during a robbery or kidnapping, such that defendant should be any more deserving of death than the perpetrator of the latter crime. (See People v. Rodriguez (1986) 42 Cal.3d 730, 788 [230 Cal.Rptr. 667, 726 P.2d 113] [“the purpose of ‘aggravating’ and ‘mitigating’ factors is to assess the seriousness of a capital crime in relation to others of the same general character”]; cf. Gregg v. Georgia (1976) 428 U.S. 153, 201 [49 L.Ed.2d 859, 890, 96 S.Ct. 2909].) It is precisely because the words “heinous, atrocious or cruel” do not provide a jury with constitutionally sufficient guidance to separate those murders for which the death penalty is a possibly appropriate penalty from those for which it is not, that the special circumstance described in section 190.2, subdivision (a)(14) was declared invalid. (Engert, supra, 31 Cal.3d 797.) Similarly, the language of section 190.2, subdivision (a)(10) itself makes clear that a witness-murder special circumstance does not exist where the crime to which the victim was a witness is the crime during the course of which the victim was killed. (See ante, fn. 5, p. 645; maj. opn., ante at p. 631.) Defendant in this case was precluded from arguing that the circumstances of his crime did not necessarily militate in favor of a sentence of death by findings, rendered under two concededly invalid or inapplicable provisions, that certain aspects of his offense were not only aggravating but sufficient to elevate him into the category of death-eligibility. These improper findings may well have affected the jury’s verdict.
I also disagree with the majority’s finding that the admission of defendant’s in-custody threat to kill a police officer was harmless error. (Maj. opn., ante, at p. 636; see People v. Boyd (1985) 38 Cal.3d 762 [215 Cal.Rptr. 1, 700 P.2d 782].) The prosecutor put on only two witnesses at the penalty phase: one who testified to an incident connected with an earlier, drug-related arrest and one who testified to defendant’s threatening statement. In addition, the prosecutor put on evidence of prior felony convictions for auto theft, attempted drug manufacture and weapons possession. Other than the threat, however, none of the evidence presented involved violence or threats of violence. Thus this erroneously admitted penalty evidence may have colored significantly and unfavorably the jury’s view of defendant’s past *648actions and of his continued dangerousness if imprisoned rather than executed.
While the question of prejudice is admittedly close, there is a reasonable possibility that the combined effect of (1) the jury’s consideration of three invalid special circumstances, including two that were nonduplicative of the special circumstance properly found, and (2) the admission of defendant’s threatening statement, was to tip the jury’s decision in favor of death. The penalty should therefore be reversed.
Appellant’s petition for a rehearing was denied July 28, 1988. Broussard, J., was of the opinion that the petition should be granted.
The statutory aggravating circumstances in the Georgia law under consideration in Zant were roughly analogous to California’s special circumstances inasmuch as the jury had to find at least one such circumstance to exist before considering the defendant for the death penalty. (462 U.S. at pp. 866, 870-872 [77 L.Ed.2d at pp. 243, 245-247].)
“In Georgia, unlike some other States, the jury is not instructed to give any special weight to any aggravating circumstance, to consider multiple aggravating circumstances any more significant than a single such circumstance, or to balance aggravating against mitigating circumstances pursuant to any special standard. Thus, in Georgia, the finding of an aggravating circumstance does not play any role in guiding the sentencing body in the exercise of its discretion, apart from its function of narrowing the class of persons convicted of murder who are eligible for the death penalty.” (462 U.S. at pp. 873-874 [77 L.Ed.2d at pp. 247-248], fn. omitted, italics added.)
All further statutory references are to the Penal Code.
In Barclay v. Florida (1983) 463 U.S. 939 [77 L.Ed.2d 1134, 103 S.Ct. 3418], the court again upheld a death sentence based in part on an improperly considered aggravating circumstance, this time under the Florida statute. That law, unlike the Georgia statute at issue in Zant, supra, 462 U.S. 862, was a “weighing” statute like California’s, in the sense that it included an instruction to the sentencer (the trial judge under the Florida statute) to weigh certain statutory aggravating and mitigating circumstances in determining whether to impose death in a given case. (Barclay, supra, 463 U.S. at pp. 952-953, 954 [77 L.Ed.2d at pp. 1145-*6451147].) However, unlike the aggravating circumstance under consideration in Zant, the one at issue in Barclay (defendant’s criminal record) did not suffer from any federal constitutional defect (Barclay, supra, at p. 951, fn.8 [77 L.Ed.2d at p. 1144]); rather its consideration was simply improper under state law because it was a circumstance not enumerated in the statute. (Id., at p. 956 [77 L.Ed.2d at p. 1148].) This distinguished Barclay from Zant (Barclay, supra, at p. 951, fn. 8 [77 L.Ed.2d at p. 1144]), but it also left unaddressed the situation expressly left open in the earlier case: whether the court would uphold a death verdict imposed under a “weighing” statute where the sentencing decision was based in part on a constitutionally invalid aggravating circumstance. (Zant, supra, 462 U.S. at p. 890 [77 L.Ed.2d at p. 258]; see Pascucci, et al., Capital Punishment in 1984: Abandoning the Pursuit of Fairness and Consistency (1984) 69 Cornell L.Rev. 1129, 1181.)
Subdivision (a)(10) provides that a special circumstance exists where the murder victim was (1) a witness to a crime (other than the crime during the commission of which the victim was killed) who was intentionally killed for the purpose of preventing his or her testimony in any criminal proceeding or (2) a witness to a crime who was intentionally killed in retaliation for testifying in a prior criminal proceeding.
The financial-gain special circumstance, of course, while improperly found in this case, was duplicative in the sense that it was based on circumstances underlying the validly found felony-murder (kidnapping for robbery) special-circumstance finding.
The prosecutor alluded to the excessive special-circumstance findings four times during his closing argument. “The murder of Kevin Thorpe, kidnapped, to rob him, killed for financial gain, killed to prevent his testimony, killed to prevent this day. And indeed heinous, atrocious, cruel, depraved behavior. This has already been decided. It’s not a matter for determination of [sic] whether these circumstances exist. The point now is what could possibly, possibly come into this case to soften what we know [defendant] did. What is there to weigh against the propriety, against the rightness of the maximum punishment? [ft] The circumstances of the crime and the existence of those special circumstances, those four special circumstances that you found to be true? The circumstances of this crime these kidnappings, robberies, possession of these weapons.? This murder? What weighs against this?” (Italics added.) Later, following a discussion of a number of the statutory mitigating factors, he argued: “Did these—are there mitigating circumstances that are even to be considered on the same scale with this heinous murder for financial gain and to prevent testimony! What is there that’s even considerable in this case compared to those crimes and the murder of Kevin Thorpe? Nothing in this evidence is on the scale to outweigh that aggravation. . . .” (Italics *647added.) Then: “The man is calm, calculated, careful. He decides to do these things. He has [we] decided in a series of events that took place 13 months ago, he decided to end it all for Kevin Thorpe. In a series of events, exhibiting what sounds like incredible calmness, for these purposes of gain, to prevent testimony, to keep from getting caught, but there are indications that that consciousness was present before the crimes even started. [‘]We will do this sort of thing and then in order to keep from being caught we will do away with this person.[’]” (Italics added.)