In People v. Wilson (1947) 78 Cal. App. 2d 108 [177 P.2d 567], the defendant was convicted of negligent homicide in violation of section 192. At that time former section 192 provided, in relevant part, "Manslaughter is the unlawful killing of a human being without malice. It is of three kinds: 3. In the driving of a vehicle: (a) In the commission of an unlawful act, not amounting to felony, with gross negligence; or in the commission of a lawful act which might produce death, in an unlawful manner, and with gross negligence. (b) In the commission of an unlawful act, not amounting to felony, without gross negligence; or in the commission of a lawful act which might produce death, in an unlawful manner, but without gross negligence." (Stats. 1945, ch. 1006, 1, pp. 1942-1943, italics added; see 192, subd. (c)(1), (2) [containing essentially same language].) On appeal the defendant noted that under section 20, all crimes require the concurrence of act and intent or "criminal negligence." Section 20 provides, "In every crime or public offense there must exist a union, or joint operation of act and intent, or criminal negligence." He claimed that former section 192, subdivision 3(b), was invalid because the language italicized above proscribed ordinary, rather than criminal, negligence. (People v. Wilson, supra, 78 Cal. App. 2d at p. 112.)