Had the trial court in this case given an instruction that a fetus need not be viable under Penal Code section 187, subdivision (a) (hereafter section 187(a)), or had the law in California been ¡settled that, for purposes of section 187(a), a viable fetus meant a fetus with a “probability” or a “reasonable likelihood” of survival outside the womb, then I would not hesitate in joining the lead opinion to reverse defendant’s conviction. As it stands, however, neither is the case, Therefore, while I concur in the holding that viability of a fetus is not required under section 187(a), I must dissent from the decision to reverse.
As the lead opinion points out, the trial court below instructed the jury that to find defendant guilty of fetal murder under section 187(a), it must find that the fetus was viable. Inasmuch as our decision today holds that fetal viability is not a requirement of section 187(a), the instruction given inured to defendant’s benefit.
The trial court further instructed: “A fetus is viable when it has achieved the capability for independent existence; that is, when it is possible for it to survive the trauma of birth, although with artificial medical aid.”1 (Italics added.) Although fetal viability is not even a requirement under section 187(a), the lead opinion finds that the court prejudicially erred in defining viability in terms of “possible” survival, and overturns defendant’s conviction.
This approach makes no sense. In finding that this definitional instruction was in error, the lead opinion is purporting to decide an issue that was unsettled both at the time defendant acted and at the time of his trial. (See post, pp. 819-821.) In effect, the lead opinion wanders into a wonderland to *819decide what the law might be had it not been for today’s holding rejecting the viability limitation.
Rather than venture into a fictitious world, I believe we should focus on whether defendant’s due process rights were violated by the giving of an instruction that defined viability in terms of possible survival. Since the unsettled status of previous case law precludes any determination whether the trial court’s instructions constituted error, we should instead look to whether the trial court’s reliance on the challenged definition was an unforeseeable judicial enlargement of section 187(a). (See Bouie v. City of Columbia (1964) 378 U.S. 347, 353 [12 L.Ed.2d 894, 899-900, 84 S.Ct. 1697].) I conclude it was not
There are at least three reasons why the trial court’s definition of viability did not amount to an unforeseeable judicial enlargement of the fetal murder statute. First, although at the time defendant acted some Courts of Appeal had inferred a viability limitation to section 187(a), none had directly addressed whether a viable fetus means a fetus with a probability or a reasonable likelihood of survival outside the womb, as opposed to one with only a possibility of survival (i.e., People v. Smith (K.A.) (1976) 59 Cal.App.3d 751 [129 Cal.Rptr. 498] [hereafter K.A. Smith]; People v. Apodaca (1978) 76 Cal.App.3d 479 [142 Cal.Rptr. 830] [hereafter Apodaca]; People v. Smith (R.P.) (1987) 188 Cal.App.3d 1495 [234 Cal.Rptr. 142] [hereafter R.P. Smith]; People v. Henderson (1990) 225 Cal.App.3d 1129 [275 Cal.Rptr. 837] [hereafter Henderson]). Second, two courts had expressed the view that a viable fetus means one that has a possibility of survival (see Apodaca, supra, 76 Cal.App.3d at p. 489; Henderson, supra, 225 Cal.App.3d at pp. 1157-1158). Third, this court indicated in 1989—two years before the conduct in this case was undertaken—that we would consider the propriety of an instruction implying that a fetus is deemed viable when it is possible for it to survive if and when we were faced with a case involving a fetus with less than a 50 percent likelihood of survival (see People v. Hamilton (1989) 48 Cal.3d 1142, 1171-1172 [259 Cal.Rptr. 701, 774 P.2d 730] [hereafter Hamilton]). Thus, the definition of viability was an open question in California.
As indicated above, two Courts of Appeal, like the trial court below, posited that a viable fetus means a fetus that has a possibility of survival (see Apodaca, supra, 76 Cal.App.3d at p. 489 [Fifth App. Dist.];2 Henderson, supra, 225 Cal.App.3d at pp. 1157-1158 [First App. Dist., Div. Three], citing *820Apodaca), as contrasted to a fetus that has a probability or a reasonable likelihood of survival.
It is likely that the court in Apodaca, supra, 76 Cal.App.3d 479, spoke in terms of possible survival because Roe v. Wade (1973) 410 U.S. 113 [35 L.Ed.2d 147, 93 S.Ct. 705] referred to viability as the time when a fetus is “potentially able” to live outside the womb, albeit with artificial aid, and has “capability of meaningful life.” (See 410 U.S. at pp. 160, 163 [35 L.Ed.2d at pp. 181-182].) However, after Apodaca, supra, the United States Supreme Court, purporting to reiterate its previous view, stated that viability, or capability of meaningful life, was reached when in the judgment of the pregnant woman’s attending physician, “there is a reasonable likelihood of the fetus’ [sic] sustained survival outside the womb, with or without artificial support.” (Colautti v. Franklin (1979) 439 U.S. 379, 388 [58 L.Ed.2d 596, 605, 99 S.Ct. 675], italics added [hereafter Colautti].) Subsequently, Henderson, supra, 225 Cal.App.3d 1129, held that section 187(a) was not unconstitutionally vague and therefore did not violate due process principles. In recognizing that the concept of viability was well established in the context of section 187, Henderson cited to the Apodaca definition of viability. (Henderson, supra, 225 Cal.App.3d at pp. 1157-1158.) Although Henderson did not specifically address the reasonable likelihood language referred to in Colautti, it did conclude that Colautti had no application to the construction of section 187(a) (225 Cal.App.3d at p. 1158.)
Taken as a whole, these decisions indicate that, even though a fetus must have a reasonable likelihood of sustained survival outside the womb for purposes of various abortion issues, a fetus must simply have a possibility of survival for purposes of California’s fetal murder statute.3 Apodaca and Henderson thus put defendant on sufficient notice that even with an implied *821viability limitation, some California courts were of the view that section 187(a) proscribed the unlawful killing of fetuses having only a possibility of survival. Defendant could therefore reasonably anticipate that his conduct would be proscribed. (See Rose v. Locke (1975) 423 U.S. 48, 50 [46 L.Ed.2d 185, 188, 96 S.Ct. 243].)
Our statements in Hamilton, supra, 48 Cal.3d 1142, provide yet another reason for finding against defendant on the due process issue. In Hamilton, a defendant contended that the trial court gave a jury instruction that improperly implied that a fetus is viable if capable of being born alive, even if it could not have survived for a sustained period outside the mother’s womb. In fact, it appears that the allegedly erroneous instruction in Hamilton was based in part on the “possibility” language of Apodaca, supra, 76 Cal.App.3d at page 489, and that the defendant had specifically argued that the instruction was contrary to Colautti, supra, 439 U.S. at page 388 [58 L.Ed.2d at p. 605]. (Hamilton, supra, 48 Cal.3d at p. 1171.) Although we expressly declined to address the defendant’s claim on the merits because there was uncontroverted evidence that the subject fetus had attained viability under any test, we noted: “The 1970 amendment extending murder to fetuses (§ 187, subd. (a); Stats. 1970, ch. 1311, § 1, p. 2440) contained no viability proviso. As amended, section 187, subdivision (a) simply defines murder as ‘the unlawful killing of a human being, or a fetus, with malice aforethought.’ The Courts of Appeal have inferred a viability limitation in light of the subsequent abortion cases, which first recognized a woman’s constitutional right to terminate her pregnancy before the fetus becomes viable. (See, e.g., Smith, supra, 59 Cal.App.3d at pp. 756-757.)” (Id., at pp. 1171-1172, fn. 18.) Hamilton thus highlighted the fact that we did not accept or approve of the implied viability limitation, and signaled our intent to address both this issue and the possibility/probability issue if and when presented with the type of facts involved here.
Affirmance of defendant’s conviction is fully consistent with our decision in People v. King (1993) 5 Cal.4th 59 [19 Cal.Rptr.2d 233, 851 P.2d 27].. which, as the majority points out, overruled In re Culbreth (1976) 17 Cal 3d 330 [130 Cal. Rptr. 719, 551 P.2d 23] (hereafter Culbreth). In People v. King, supra, 5 Cal.4th 59, the Attorney General argued that our overruling of Culbreth should apply to the defendant because the plain words of the subject statute, together with explicit criticisms of Culbreth by various Courts of Appeal, gave fair warning that we might reconsider our stated position. (5 Cal.4th at pp. 79-81.) We rejected the argument, observing: “The mere possibility that this court might reconsider its own precedent is not the equivalent of actually overruling it.” (Id., at p. 80.)
*822The situation before us is clearly distinguishable. The challenged jury instruction defining viability in terms of “possible” survival is grounded in the language of two appellate decisions. Prior to the time defendant acted, no appellate court in California had ever held that for purposes of section 187(a), viability means a probability or reasonable likelihood of survival. Finally, Hamilton, supra, 48 Cal.3d at pages 1171-1172, gave ample warning to defendant that we would consider the possibility/probability issue in a case presenting the appropriate facts.
Under these circumstances, defendant cannot credibly claim that the jury instructions given in this case represented an unforeseeable judicial enlargement of section 187(a). Accordingly, defendant’s due process rights were not violated by their use.
I would affirm the conviction.
George, J., concurred.
In addition, the trial court instructed the jury that “[s]urviving the trauma of birth does not mean momentary survival, but requires survival at least through the 28 day neonatal period.” Therefore, the instructions as a whole did not, as the lead opinion suggests, tell the jury that a fetus with a possibility of survival could refer to “a fetus incapable of survival outside the womb for any discernible time.” (Lead opn., ante, p. 814.)
Tbe precise statement in Apodaca was: “A fetus is viable when it has achieved the capability for independent existence; ... a fetus is deemed viable when it is possible for it to survive the trauma of birth, although with artificial medical aid.” (76 Cal.App.3d at p. 489, *820italics added.) Strictly speaking, however, this statement appears to be dicta—the court did not reach the question whether the trial court had erred in failing to define the word “fetus” in terms of viability because uncontroverted medical testimony had indicated during trial that the fetus was viable at the time it was murdered. Furthermore, while the court gave its definition of viability in the context of holding that the determination of fetal viability is dependent upon the peculiar circumstances of each case, it did not address the possibility/ probability distinction.
It is unclear whether the other Court of Appeal decisions are inconsistent with Apodaca and Henderson. K.A. Smith, supra, 59 Cal.App.3d 751, an early case in which it was stipulated that the subject fetus was nonviable (id., at p. 754), simply held that the destruction of a nonviable fetus could not constitute murder under section 187(a) (59 Cal.App.3d at pp. 756-757). However, in rejecting the Attorney General’s argument that the concept of viability was too vague to be serviceable, the court in K.A. Smith stated that the definition of viability was well established, meaning “ ‘having attained such form and development of organs as to be normally capable of living outside the uterus.’ ” (Id., at p. 758, citing Webster’s New Internat. Dict. (3d ed. 1966) p. 2548.) The court, however, had not been asked to address the possibility/probability distinction. R.P. Smith, supra, 188 Cal.App.3d 1495, also did not *821specifically discuss the possibility/probability issue, but did seem to equate the term “viability” with “85 percent chance to survive independent of the womb.” (Id., at p. 1516.)