I agree that the enactment of Penal Code section 1203.066, which renders eligible for probation persons convicted of lewd or lascivious conduct who “honestly and reasonably believed the victim was 14 years old or older” is persuasive evidence that in the eyes of the Legislature such a belief is not a defense to the crime.1 What troubles me is the notion that a person who acted with such belief, and is *650not otherwise shown to be guilty of any criminal conduct,2 may not only be convicted but be sentenced to prison notwithstanding his eligibility for probation when it appears that his belief did not accord with reality. To me, that smacks of cruel or unusual punishment.3
I fully accept that “fault” even for purposes of the criminal law, may at times be predicated upon conduct, short of “intentional,” which exposes others to substantial and unjustified risks.4 I recognize also that our legal system includes certain “strict liability” crimes, but generally these are confined to the so-called “regulatory” or “public welfare” offenses, which “do not fit neatly into any of such accepted classifications of common-law offenses, such as those against the state, the person, property, or public morals. . . . Many violations of such regulations result in no direct or immediate injury to person or property but merely create the danger or probability of it which the law seeks to minimize.” (Morissette v. United States (1952) 342 U.S. 246, 255-256 [96 L.Ed. 288, 296, 72 S.Ct. 240].) Moreover, with respect to such crimes, “The accused, if he does not will the violation, usually is in a position to prevent it with no more care than society might reasonably expect . . . from one who assumed his responsibilities. Also, penalties commonly are relatively small, and conviction does no grave damage to an offender’s reputation.” (Id., at p. 256 [96 L.Ed.2d at p. 297], italics added.)
Even in the regulatory context, “judicial and academic acceptance of li*651ability without fault has not been enthusiastic.” (Jeffries & Stephan, Defenses, Presumptions, and Burden of Proof in the Criminal Law (1979) 88 Yale L.J. 1325, 1373.) And “with respect to traditional crimes, it is a widely accepted normative principle that conviction should not be had without proof of fault. At least when the offense carries serious sanctions and the stigma of official condemnation, liability should be reserved for persons whose blameworthiness has been established.” (Id., at pp. 1373-1374, fn. omitted.)
Commentators have suggested that this normative principle has a home in constitutional law (e.g., Dubin, Mens Rea Reconsidered: A Plea for a Due Process Concept of Criminal Responsibility (1966) 18 Stan.L.Rev. 322; Hippard, The Unconstitutionality of Criminal Liability Without Fault: An Argument for a Constitutional Doctrine of Mens Rea (1973) 10 Houston L.Rev. 1039; Packer, The Aims of the Criminal Law Revisited: A Plea For a New Look at “Substantive Due Process” (1971) 44 So.Cal.L.Rev. 490), and decisions of both the United States Supreme Court and this court lend some support to that premise. For example, in Robinson v. California (1962) 370 U.S. 660, 666-667 [8 L.Ed.2d 758, 763, 82 S.Ct. 1417], a California statute making it a misdemeanor punishable by imprisonment for a person to “be addicted to the use of narcotics” even though he had never touched any narcotic drug within the state or been guilty of any irregular behavior there, was held to inflict cruel and unusual punishment in violation of the Fourteenth Amendment. (Cf. Powell v. Texas (1968) 392 U.S. 514, 533 [20 L.Ed.2d 1254, 1268, 88 S.Ct. 2145].)
In Burg v. Municipal Court (1983) 35 Cal.3d 257 [198 Cal.Rptr. 145, 673 P.2d 732], this court unanimously upheld, against due process constitutional attack, a statute which makes it an offense for “any person who has 0.10 percent or more, by weight, of alcohol in his or her blood to drive a vehicle.” (Veh. Code, § 23152, subd. (b).) The heart of that attack, though phrased in familiar terms of “vagueness” and “lack of due notice,” was that a person might be unaware that his blood alcohol level exceeds the proscribed limit, and thus might be morally “innocent.” In response, we observed that it requires “more than a small amount of alcohol” to produce a . 10 blood-alcohol reading, and that readily available and widely disseminated charts “show with reasonable certainty the number of different alcoholic beverages necessary for a particular individual to reach [that level].” (Burg v. Municipal Court, supra, 35 Cal.3d at pp. 271-272.) “The very fact that he has consumed a quantity of alcohol should notify a person of ordinary intelligence that he is in jeopardy of violating the statute.” {Id., at p. 271.) Thus, “[o]ne who drives a vehicle after having ingested sufficient *652alcohol to approach or exceed the level proscribed is neither ‘innocent’ . . . nor is he without ‘fair warning’. ... It is difficult to sympathize with an ‘unsuspecting’ defendant who did not know if he could take a last sip without crossing the line, but who decided to do so anyway.” (Ibid.)
While upholding the statute’s validity, we nevertheless recognized the possibility of constitutional problems arising out of its application in particular cases. Observing that Burg involved a facial attack on the statute following overruling of demurrer, we stated: “We therefore need not consider to what extent in particular cases fundamental notions of due process would permit a defendant to show, for example, that he did not knowingly or voluntarily drive or consume alcohol. ” (35 Cal.3d at p. 266, fn. 10, italics added; see also State v. Guest (Alaska 1978) 583 P.2d 836, 838 [“it would be a deprivation of liberty without due process of law to convict a person of a serious crime without the requirement of criminal intent”]; but cf. Com. v. Miller (1982) 385 Mass. 521 [432 N.E.2d 463, 466].)
The Legislature has itself determined, in section 1203.066, that a person’s belief in the victim’s age being over 14 may be not only honest but reasonable. No doubt the standard of what is reasonable must be set relatively high in order to accomplish the legislative objective of protecting persons under 14 years of age against certain conduct. Perhaps it is not enough that a person “looks” to be more than 14; perhaps there is a duty of reasonable inquiry besides. At some point, however, the belief becomes reasonable by any legitimate standard, so that one would say the defendant is acting in a way which is no different from the way our society would expect a reasonable, careful, and law-abiding citizen to act.
At that point, it seems to me, the imposition of criminal sanctions, particularly imprisonment, simply cannot be tolerated in a civilized society.
In this case we cannot ascertain from the record on appeal whether the trial court found some merit in defendant’s claim that he honestly and reasonably believed the victim to be over 14 years of age. Since the court apparently considered defendant eligible for probation it is possible that the claim was given credence. If so, and defendant’s conduct was in other respects that which we would expect of a reasonable, careful, and law-abiding citizen, I would conclude that imposition of a sentence of imprisonment on defendant is impermissible. Inasmuch as the record is inadequate to resolve either question, however, I would remand for a new probation and sentence hearing at which the court, if probation is again denied, should make express findings as to whether defendant honestly and reasonably believed the victim to be over 14 years of age and, if so, whether his conduct with her *653otherwise reflected that mens rea traditionally accepted as a prerequisite to the imposition of serious penal sanctions.
I do not agree that legislative intent to eliminate good faith mistake of fact as a defense can be inferred from the imposition of relatively higher penalties for that crime. (Maj. opn., ante, at pp. 648-649.) On the contrary, as this court has stated in connection with the crime of bigamy: “The severe penalty imposed ... the serious loss of reputation conviction entails, the infrequency of the offense, and the fact that it has been regarded ... as a crime involving moral turpitude, make it extremely unlikely that the Legislature meant to include the morally innocent to make sure the guilty did not escape.” (People v. Vogel (1956) 46 Cal.2d 798, 804 [299 P.2d 850].)
The People suggest that defendant was at least guilty of “sexual intercourse accomplished with a female not the wife of the perpetrator, where the female is under the age of 18 years.” (Pen. Code, § 261.5.) Defendant was neither charged nor convicted of that offense, however, and it is by no means clear from the record that he had sexual intercourse with the victim.
Defendant has not made this argument; thus, I do not fault my colleagues for failing to consider it.
Penal Code section 20 provides: “In every crime or public offense there must exist a union, or joint operation of act and intent, or criminal negligence. ” (Italics added.) In the context of negligent homicide, it has been held that ordinary negligence will not suffice. “The conduct must be aggravated or reckless; that is, it must be such a departure from what would be the conduct of an ordinarily prudent person under the same circumstances as to be incompatible with a proper regard for human life. The conduct must show an indifference to the consequences, and this has been said to require knowledge, actual or imputed, that the act tends to endanger another’s life.” (People v. Peabody (1975) 46 Cal.App.3d 43, 47 [119 Cal.Rptr. 780]; see People v. Penny (1955) 44 Cal.2d 861, 879 [285 P.2d 926].)
For differing views as to the propriety of predicating criminal liability upon ordinary negligence, compare Hall, Negligent Behavior Should Be Excluded From Penal Liability (1963) 63 Colum.L.Rev. 632, with Fletcher, The Theory of Criminal Negligence: A Comparative Analysis (1971) 119 U.Pa.L.Rev. 401.